SIX ENGINE l-A-l 232-258 Cubic Inch Displacement

Page Page ENGINE ASSEMBLY 1 Installation 12 Description 1 TIMING CHAIN COVER 12 Identification 1 Removal 13 Diagnosis Guide 2 Installation 13 Mounting 3 Oil Seal Replacement 13 Removal 3 TIMING CHAIN 14 Installation 4 Checking Valve Timing 14 LUBRICATION SYSTEM 4 Removal 14 Lubrication Circuit 4 Installation 14 5 AND BEARINGS 14 Oil Pump 5 Measuring Lobe Lift 14 Oil Pressure Relief Valve 5 Removal 14 POSITIVE VENTILATION 6 Inspection 15 Air Inlet Filter 6 Installation 15 PCV Valve 6 OIL PAN 15 COVER AND 6 Removal 15 Removal 6 Installation 15 Installation 7 OIL PUMP 15 AND SHAFT ASSEMBLY 7 Removal 15 Removal and Disassembly 7 Disassembly and Inspection 16 Cleaning and Inspection 7 Assembly and Installation 16 Assembly and Installation 7 REAR OIL SEAL 16 VALVE SPRING AND/OR VALVE STEM OIL DEFLECTOR.. 7 Removal and Installation 16 Removal and Testing 8 BEARINGS 17 Installation 8 Removal and Inspection 17 AND EXHAUST MANIFOLDS 8 Measuring Bearing Clearance With Plastigage 17 Removal and Cleaning 8 Measuring Connecting Rod Journal With a Micrometer 17 Installation 8 Installation 18 CYLINDER HEAD AND GASKET 8 CONNECTING ROD AND ASSEMBLIES 18 Removal 9 Removal 18 Cleaning and Inspection 9 Cylinder Conditioning 18 Installation 9 18 CYLINDER HEAD RECONDITIONING 9 Piston Rings 18 Disassembly 9 Connecting Rods and Piston Pins 19 Cleaning and Inspection 10 Installation 20 Valve Refacing 10 MAIN BEARINGS 20 Valve Seat Refacing 10 Removal and Inspection 20 Valve Stem to Guide Clearance 10 Measuring Bearing Clearance With Plastigage 21 Assembly 10 Installation 21 HYDRAULIC VALVE 10 CRANKSHAFT 21 Noise Diagnosis 11 Replacement 21 Removal and Disassembly 11 Checking End Play 21 Cleaning and Inspection 11 SHORT ENGINE ASSEMBLY 21 Assembly and Testing 12 AND RING GEAR ASSEMBLY 21 Installation 12 SPECIFICATIONS 22 VIBRATION DAMPER 12 TOOLS 23 Removal 12

ENGINE ASSEMBLY from the rear of the engine. The letter contained in the code Seven two-piece main bearings are identifies the engine by cubic inch Description used to support the crankshaft and the displacement, type and The 232 and 258 CID six cylinder camshaft is supported by four one- . engines incorporate an overhead valve piece line bored bearings. The letters used are coded as follows: system in which the rocker arms oper­ Comp. ate on a common shaft. Code CID Carb. Ratio Identification The cylinders are numbered from A (Standard) 258 IV 8. 0: 1 front to rear with a of The Engine Code is located on a B (Optional) 258 IV 7. 6: 1 1-5-3-6-2-4. The crankshaft rotates in machined surface of the block between E (Standard) 232 IV 8. 0: 1 a counterclockwise direction, viewed number two and three cylinders. F (Optional) 232 IV 7. 5: 1 l-A-2 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

DIAGNOSIS GUIDE

Conditions and Probable Causes

Cannot Engine

Electrical System Trace circuits for faulty electrical units. Coolant Leak into Cylinder Remove spark plugs to check for coolant in cylinders. Crank with plugs removed. Cylinder heads must be removed to check , block, and head for a source of coolant leak. If permanent anti-freeze en­ tered engine, complete disassembly will have to be accomplished. Mechanical Seizure Recondition.

Engine Will Crank Normally but Will Not Start

Ignition System Check spark plugs and secondary circuit energy available at spark plugs. Fuel System

air horn for choke condition. If water is present, clean out and substitute with a supply of new fuel. Ignition or Valve Timing Check ignition and valve timing.

Engine Starts and Runs for Short Periods Only

Fuel System Check and fuel lines from for intermittent or constant restricting material or defect. FIGURE 1 - Engine Code Check for leaky condenser and coil Typical Location secondary. Check for faulty distribu­ tor contacts, ignition switch, and all All engines built for sale in Cali­ FIGURE 2 — Engine Letter Code connecting wires including battery fornia are painted "red. " All other connections. engines are painted "blue. " l0WS: Induction System In the machining of cylinder blocks Single letter.. "B" Cylinder Check air leaks which may be too and , it is sometimes neces­ bore —. 010" Oversize severe after choke enrichment is re­ sary to machine the cylinder bores to Single letter.. "M" Main duced. . 010" oversize, and the crankshaft bearings —. 010" Undersize main bearing journals or crank pins to Single letter.. "P".... Connecting Check exhaust system for restrictions. . 010" undersize. rod bearings —. 010" Undersize These engines are marked with a Double letters.. "PM" Main Engine Runs but Mis-fires at single or two letter code (Fig. 2). and connecting rod bearings — Low Speed Only The code is located on a boss di­ . 010" Undersize rectly above the oil filter. Single letter.. "C" Camshaft Fuel System The letters used are coded as fol- block bores -. 010" Oversize Check for dirty passages and jets in SIX CYLINDER ENGINE l-A-3 232-258 Cubic Inch Displacement

the idle circuit. Cooling System Exhaust System Ignition System Thermostat not permitting proper Back pressure and leakage into the Check heat range and operating temperature. intake system. gap. Engine Resistance Induction System Bearing and and piston Mounting Check for intake manifold air leaks. fit for oil clearance. Check for air leaks from units con­ Rolling Resistance of Vehicle Resilient rubber mounting cushions nected to intake manifold. Brakes dragging. Soft tires. Wheel support the engine and transmission at Valves alignment. Wheel bearings. Clutch three points. A cushion is located at Check for poor valve seating. or transmission slippage. each side on the center line of the en­ gine, (Fig. 3), with the rear supported Engine Runs but Misses at All Speeds Engine Rough Running at Higher by a cushion between the transmission Speeds extension housing and the rear sup­ Fuel System port crossmember. Removal or replace­ Dirt in carburetor or water in the Ignition System ment of any cushion may be accom­ fuel system. Spark plug gap and heat range. plished by supporting the weight of Ignition System Ignition timing. centrif­ the engine or transmission at the area Spark plugs, wiring, capacitor, coil, ugal and vacuum advance units. of the cushion. and ignition system wiring. polarity. switch. Fuel System Removal Valves Improper fuel mixtures. Poor valve seating — sticking valves. Fuel Induction System The engine is removed without the Cooling System Severe air leaks into intake system. transmission and bell housing. Coolant leak into intake sections or Valves and Camshaft On the Commando, Wagoneer and cylinders. Sticky valves. Incorrect valve lift. Truck the hood must be removed. Mark Camshaft the hinge locations at the hood panel Worn lobes on camshaft. Engine will not Respond to Fast Positive for alignment during installation. Re­ Opening of move the hood from the hinges. Engine Rough Running at Low Speeds Remove the air cleaner assembly Fuel System and drain the cooling system. Ignition System Carburetor accelerating circuits. Im­ Disconnect the upper and lower ra­ Spark plug gap and heat range. proper fuel. Throttle linkage. Re­ diator hoses. If equipped with auto­ Secondary system wiring. Distributor strictions and dirty air cleaner. matic transmission, disconnect the points or capacitor. Carbon build-up on floor of intake cooler lines from the radiator. Fuel System manifold. Idle circuits dirty. Choke sticking. Air Ignition System NOTE: If vehicle is equipped with leak below carburetor. Idle mixture Coil capacity and polarity, spark a radiator shroud, it is necessary to adjustment. plug condition, gap, and heat separate the shroud from the radiator Cooling System range. Ignition timing. Distributor to facilitate removal of the radiator Coolant system leaks into intake condition. and engine . valve ports or cylinder. Valves Poor valve seating. Exhaust System Exhaust leaks into intake passages. Exhaust back pressure.

Engine Power Not Up to Normal

Valves Valves not seating properly. Not timed properly. Rings Rings worn, broken, not seating. Fuel System Air cleaner restricted. Power mixture not proper. Ignition System Coil capacity, polarity, and distribu­ tor point spacing. Ignition timing. Exhaust System Restriction causing back pressure. l-A-4 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

Remove the radiator. engine compartment and align with the upper and lower hoses. If equipped Remove the engine fan. transmission bell housing (automatic with , connect If so equipped, remove the power transmission) or clutch housing (manual the cooler lines. steering pump and drive from the transmission). On manual transmissions, Fill the cooling system to the speci­ engine and place aside. Do not dis­ make certain the clutch shaft is aligned fied level. Inspect the engine oil level connect the power steering hoses. properly with the splines of the clutch and add oil as required. If equipped with air conditioning, driven plate. Install the air cleaner assembly. turn both service valves clockwise to Install the transmission bell housing Start the engine. Check all hose con­ the front seated position. to engine adapter plate bolts (auto­ nections for leaks. Stop the engine. Bleed the compressor refrigerant matic transmission) or the clutch hous­ If removed, install and align the charge by slowly loosening the service ing to engine bolts (manual transmis­ hood assembly. valve fittings. Disconnect the condenser sion). Tighten the bolts to the specified Install the transmission access cover, and evaporator lines from the compres­ torque. Remove the floor jack which floor mat and transfer case shift lever sor. Disconnect the receiver outlet at was used to support the transmission. boot. the disconnect coupling. Remove the If equipped with automatic trans­ condenser and receiver assembly. mission, align the marks previously LUBRICATION SYSTEM Disconnect all wires, lines, linkage made on the converter and flex plate, and hoses which are connected to the install the converter to flex plate cap A full pressure type lubrication sys­ engine. screws and tighten to the specified tem is used, except for the piston pins, Remove the oil filter. torque. which are lubricated through the con­ Remove both engine front support Install the two (2) engine adapter necting rod squirt holes and oil throw- cushion to frame retaining nuts. plate inspection covers (automatic off. Disconnect the exhaust pipe at the transmission) or the clutch housing Pressure is applied by a gear type, support bracket and . lower cover (). positive pressure pump mounted on a Support the weight of the engine Install the starter motor. boss adjacent to the number four main with a lifting device. Install the front support cushion and bearing location. Remove the front support cushion bracket assemblies to the engine, and bracket assemblies from the en­ tighten the retaining bolts to the speci­ Lubrication Circuit gine. fied torque. Remove the transfer case shift lever Lower the engine onto the frame Oil, drawn through the inlet screen boot, floor mat (if so equipped) and supports, remove the lifting device and and tube to the inlet side of the oil transmission access cover. install the front support cushion re­ pump, is driven between the gears and Remove the upper bolts securing taining nuts. Tighten the nuts to the pump body to the pressure outlet por­ the transmission bell housing to the specified torque. tion of the oi' pump where it is engine adapter plate on vehicles Connect the exhaust pipe at the routed through an oil gallery to the equipped with automatic transmission. support bracket and exhaust manifold inlet side of the full flow oil filter; and If equipped with manual transmission, using a new seal, if required. on into the main oil gallery (Fig. 4). remove the upper bolts securing the Install the oil filter. Each main bearing and camshaft bearing is lubricated by oil from the clutch housing to the engine. Connect all wires, lines, linkage and main oil gallery. Remove the starter motor. hoses which were previously discon­ Holes drilled in each connecting rod If equipped with automatic trans­ nected from the engine. journal direct lubrication to the con­ mission, remove the two (2) engine If removed, install the air condition­ necting rod bearings. Oil throw-off adapter plate inspection covers. Mark ing condenser and receiver assembly. from each connecting rod bearing lu­ the assembled position of the converter Connect the receiver outlet to the dis­ bricates the cylinder walls and piston and flex plate and remove the con­ connect coupling. Connect the con­ pins. verter to flex plate cap screws. Remove denser and evaporator lines to the the remaining bolts securing the trans­ compressor. Purge the compressor of A small channel (squirt hole) lo­ mission bell housing to the engine air as outlined in the "AIR CONDI­ cated on the numbered side of the adapter plate. TIONING" section. connecting rods and caps allows oil to If equipped with manual transmis­ lubricate the camshaft lobes, tappets, sion, remove the clutch housing lower CAUTION: Both service valves must piston pins and distributor drive gear. cover and the remaining bolts securing be open before the air conditioning The hydraulic valve tappets are fed the clutch housing to the engine. system is operated. directly from the main oil gallery. Support the transmission with a floor Lubrication is supplied to the timing jack. If removed, install the power steer­ chain and gears from the front cam- ing pump and drive belt, tighten the Remove the engine by pulling for­ shaft bearing and returned to the belt to the specified tension. ward and upward. crankcase through a cavity under the Install the engine fan and tighten front main bearing cap. Installation the retaining bolts to the specified The oil supply for the rocker arms torque. and push rods is obtained from the Lower the engine slowly into the Install the radiator and connect the number three cam bearing location, SIX CYLINDER ENGINE l-A-5 232-258 Cubic Inch Displacement

incorporates a pressure relief valve to regulate maximum pressure. Crank­ case oil enters the pump through a pick-up tube and screen assembly which is a press fit in the pump body (Fig. 6).

FIGURE 4 — Lubrication Circuit FIGURE 6 — Oil Pump Components

where oil from the main lubrication gallery is metered through a groove in the camshaft bearing surface to a gallery extending upwards to the cyl­ inder surface. At this point, the cylinder head gasket forms a seal joining the cylinder block gallery with the adjoining gallery in the cyl­ inder head. Commencing at the num­ ber five rocker arm support, the oil then flows into the rocker arm shaft to supply lubrication to the rocker arm and push rods. Holes cast in the cylinder head re­ turn the oil to the crankcase through the valve area, which in turn lubricates the tappets.

Oil Filter

A full flow oil filter, mounted on the lower right hand side of the engine, is accessible through the hood opening. A by-pass valve, incorporated in the filter mounting boss, provides a safety factor in the event the filter becomes FIGURE 5 - Oil Filter Assembly inoperative as a result of dirt or sludge Operate engine at fast idle and Oil pump removal or replacement accumulation. (Fig. 5. ) check for leaks. will not affect distributor timing as the Oil Filter Removal Tool J-22700 will distributor drive gear remains in mesh facilitate removal of the oil filter. Oil Pump with the camshaft gear. Apply a thin film of oil to the new filter gasket before installation. A positive displacement gear type Oil Pressure Relief Valve Install filter until gasket contacts the oil pump is used and is driven by the seat of the adapter. Then tighten se­ distributor shaft, which in turn is driven The oil pressure relief valve is not curely, by hand only. by a gear on the camshaft. The pump adjustable. A setting of 75 pounds l-A-6 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

maximum pressure is built into the ten­ along with the fuel-air mixture. sion of the spring. The system will work effectively as In the relief position, the valve per­ long as all component parts are free mits oil to by-pass through a passage from sludge and foreign material. in the pump body to the inlet side of The oil filler cap, which is non- the pump. vented, requires no service. The air The oil pump pick-up tube and inlet filter and the PCV valve require screen assembly is a press fit in the service at periodic mileage intervals. oil pump body. The connecting hoses should be cleaned or replaced whenever neces­ CAUTION: Do not disturb the posi­ sary. tion of the tube assembly in the pump body unless absolutely necessary. Air Inlet Filter In the event the tube is disturbed, The wire gauze air inlet filter is it must be replaced with a new tube located within the air cleaner end of assembly. the moulded rubber hose which is con­ nected between the air cleaner and FIGURE 8 — Removing Air Inlet Filter POSITIVE CRANKCASE cylinder head cover. It must be cleaned During periods of relatively high VENTILATION in kerosene at the mileage intervals , such as during idle, This system prevents crankcase recommended in the "Mechanical the valve provides a reduced air flow vapors from entering the atmosphere. Maintenance Schedule. " since crankcase vapor pressure is low During periods of relatively high NOTE: The air inlet filter must be re­ at this time and requires little venting. manifold vacuum, such as idle or cruise moved frorn inside the carburetor air The reduced air flow also assures a speeds, crankcase vapors are drawn cleaner hose prior to removing the hose. smooth idle (Fig. 9). through the cylinder head cover and The molded end of the air inlet hose PCV valve into the intake manifold will be damaged if the hose is pried out where they are burned with the fuel- with the filter in place (Fig. 8). air mixture. At this time, fresh air passing PCV Valve through the inlet filter in the connecting hose between the air cleaner and cyl­ The PCV valve is located in a rubber inder head cover, is routed through the grommet toward the rear of the cyl­ FIGURE 9 — Positive Crankcase cylinder head cover to the crankcase inder head cover and is connected to Ventilation Flow-Valve (Fig. 7). a hose through which manifold vac- The PCV valve must be replaced at the mileage intervals recommended in the "Mechanical Maintenance Sched­ ule. " It should be cleaned and tested at more frequent mileage intervals when driving under adverse conditions. A cleaned or replacement PCV valve should always be tested with PCV Valve Tester J-23111 to determine cor­ rect air flow rate (Refer to the "Emis­ sion Control" section for a complete test procedure).

CYLINDER HEAD COVER AND GASKET Removal

Remove the air cleaner and the PCV During periods of low manifold vac­ uum is routed from a fitting at the moulded hose. uum, such as heavy acceleration, the intake manifold. Disconnect the fuel and distributor flow is reversed. During periods of relatively low vacuum advance lines at the carbu­ Crankcase vapors are then drawn manifold vacuum, such as high speed retor, bend as required to allow re­ into the connecting hose between the or heavy acceleration, the valve pro­ moval of the cylinder head cover. air cleaner and cylinder head cover vides an increased air flow to vent the Disconnect all other hoses or lines and through the air cleaner element high vapor pressure which develops attached to the cylinder head cover. to the intake manifold to be burned in the crankcase. Remove the retaining screws and SIX CYLINDER ENGINE l-A-7 232-258 Cubic Inch Displacement

separate the cylinder head cover and scored or worn, they should be re­ the oil used for rocker arm lubrication gasket from the engine. placed. If the shaft is plugged by from entering the sludge which cannot be removed by through the valve guides. The oil de­ Installation cleaning, it should be replaced. flectors should be replaced whenever valve service is performed or if the Place the gasket on the cylinder IMPORTANT: Always check for ade­ rubber has become hard and brittle. head cover flange making certain the quate oil supply through the oil passage The valve spring is held in place gasket tabs are positioned in the cut at number five (numbered from front on the valve stem by a retainer and out openings of the cover. to rear) rocker arm support whenever a set of valve locks. The locks can be Position the cylinder head cover and the rocker arms or shaft are worn due removed only by compressing the valve gasket on the engine. Install the retain­ to oil starvation. spring. Whenever valve springs are re­ ing screws and tighten to the specified Inspect the push rod contact surface moved, they should be tested for torque. of each rocker arm. Replace the rocker correct tension and replaced if not Connect the fuel and distributor vac­ arm as well as the mating push rod if within specifications. uum advance lines to the carburetor. excessively worn. Valve springs and oil deflectors can Connect all other hoses or lines Inspect the valve stem contact sur­ be removed without removing the cyl- which were previously disconnected face of each rocker arm. from the cylinder head cover. Reface the contact surface if minor Install the air cleaner and connect pitting has occurred. Replace the the PCV moulded hose. rocker arm if it is deeply pitted.

ROCKER ARM AND SHAFT Assembly and Installation ASSEMBLY Assemble the rocker arms, spacers, Removal and Disassembly retainers, retaining bolts and oil de­ Remove the cylinder head cover and flector on the rocker arm shaft in the gasket. same order as removed. If the correct Loosen the retaining bolts from the order is not known, refer to the dis­ cylinder head and remove the rocker assembled view in Figure 10. arm and shaft assembly, including the NOTE: The oil holes of the rocker retaining bolts. arm shaft must face the cylinder head. Remove the roll pin and spring washer from one end of the rocker Use two rubber bands to hold the arm shaft. rocker arms in position as shown in Remove the rocker arms, spacers, Figure 11 and install the rocker arm retainers, retaining bolts and oil de­ and shaft assembly to the cylinder flector and place on a bench in the head. Make certain the push rods are same order as removed. correctly aligned with the rocker arms before tightening the retaining bolts. Cleaning and Inspection Work from the center of the rocker arm shaft outward and tighten the Clean all parts with a good cleaning retaining bolts evenly until the speci­ solvent while retaining the order in fied torque is obtained. which they were removed from the Install the cylinder head cover and rocker arm shaft. Use compressed air gasket. to clean out the oil passages in the rocker arms and shaft. VALVE SPRING AND/OR Inspect each rocker arm mounting VALVE STEM OIL DEFLECTOR surface and the rocker arm shaft at each rocker arm location. If the shaft Rubber valve stem oil deflectors are or any rocker arms are excessively installed on each valve stem to prevent l-A-8 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement inder head. Refer to "Cylinder Head tainer from the cylinder head. Remove surfaces of the intake manifold to Reconditioning" for removal procedure the oil deflector if replacement is exhaust manifold and also between the with the cylinder head removed. required. exhaust manifold and exhaust pipe. Use Valve Spring Tester C-647 to Removal and Testing test each removed valve spring for Removal and Cleaning the specified tension values (Fig. 14). Remove the cylinder head cover and Replace all valve springs which are Remove the air cleaner and carbu­ retor. gasket. not within specifications. Remove the rocker arm and shaft Disconnect the accelerator cable assembly and the push rods. from the accelerator bellcrank. Disconnect the PCV vacuum hose NOTE: Push rods should be retained from the intake manifold. in the same order as removed. Disconnect the distributor vacuum Remove the spark plug from the hose and electrical wires at the TCS cylinder which requires valve spring solenoid vacuum valve. or oil deflector removal and install a If equipped with air conditioning, 14 mm. thread size air adapter in the disconnect the compressor and bracket spark plug hole. assembly from the intake manifold. Disconnect the exhaust pipe from NOTE: The adapter can be made the manifold flange. from the body of a spark plug from Remove the manifold attaching bolts, which the porcelain has been removed nuts and clamps; separate the intake and an air hose connection fastened to and exhaust manifold from the engine the body of the spark plug. as an assembly. Discard the gasket. Connect an air hose to the adapter If either manifold is to be replaced, and maintain at least 90 PSI in the separate the manifolds at the riser area. cylinder to hold the valves against their Installation seats. Clean the mating surfaces of the Use Valve Spring Remover and In­ If removed, install the oil deflector manifolds and the cylinder head. staller Tool J-21931 to compress the on the valve stem. Installation valve spring and allow removal of the IMPORTANT: The valve springs must valve locks (Fig. 13). be installed with the close coiled end If separated, assemble the two mani­ facing the cylinder head. folds and finger tighten the retaining nuts. Install the valve spring and retainer. Position a new intake manifold gas­ Compress the valve spring with Valve ket on the cylinder head and install Spring Remover and Installer Tool the manifold assembly. Tighten the J-21931 and insert the valve locks. manifold attaching bolts and nuts in Release the spring tension and remove the sequence shown in Figure 15. the tool. Tap the valve spring from Torque to specifications. side to side with a light hammer to be Install the flange gasket and connect certain the spring is seated properly the exhaust pipe to the exhaust mani­ at the cylinder head. fold flange. Disconnect the air hose and remove Install the carburetor. the air adapter from the spark plug If removed, install the air condition­ hole. Install the spark plug. ing compressor and bracket assembly Install the rocker arm and shaft as­ to the intake manifold. Install the drive sembly. belt and tighten to the specified Install the cylinder head cover and tension. gasket. Connect the distributor vacuum hose and electrical wires to the TCS sole­ INTAKE AND EXHAUST noid vacuum valve. MANIFOLDS Connect the accelerator cable and The intake and exhaust manifolds PCV hose. are mounted externally on the left side Install the air cleaner. of the engine and attached to the CAUTION: Do not compress the valve cylinder head. A gasket is used be­ CYLINDER HEAD AND GASKET springs more than required to remove tween the intake manifold and the the valve locks, as the oil deflectors Removal cylinder head, none is required for the may be damaged- exhaust manifold to cylinder head. An Drain the cooling system and dis- Remove the valve spring and re- asbestos gasket is used at the mating connect the hoses at the thermostat SIX CYLINDER ENGINE l-A-9 232-258 Cubic Inch Displacement

compound on head and block surfaces or allow sealer to enter cylinder bores.

Install the cylinder head and bolts to the block. Tighten the bolts to the specified torque following the sequence shown in Figure 16. Connect the temperature sending unit wire. Install the ignition coil and bracket assembly. Install the spark plugs and connect the spark plug wires. Install the intake and exhaust mani­ fold assembly to the cylinder head. Refer to "Intake and Exhaust Manifold Installation" for the correct torque tightening sequence. Install the push rods in the order re­ moved. FIGURE 15 — Intake Manifold Torque Sequence Install the rocker arm and shaft as­ sembly, tighten the retaining bolts to housing. stem diameter. Replace the valves if the specified torque and install the Remove the cylinder head cover and they are oversize as only standard cylinder head cover and gasket. gasket, rocker arm and shaft assem­ size valves are to be used with a Connect the hoses to the thermostat bly, and the push rods. service replacement head. If the orig­ housing and fill the cooling system to inal valves are standard size, remove the specified level. NOTE: Push rods should be retained all carbon buildup and reface the in the same order as removed. valves as outlined under "Valve Re- CYLINDER HEAD facing. " Install the valves in the cyl­ Separate the intake and exhaust RECONDITIONING manifold assembly from the cylinder inder head using new valve stem oil head. deflectors. Transfer all attached com­ The following procedures apply after Disconnect the spark plug wires and ponents from the original head which the cylinder head has been removed remove the spark plugs. are not included with the replacement from the engine. Disconnect the temperature sending head. unit wire, ignition coil and bracket as­ Apply an even coat of "Perfect Disassembly sembly from the cylinder head. Seal" sealing compound, or equivalent, Compress each valve spring with a Remove the cylinder head bolts and to both sides of the new head gasket "C" clamp type spring compressor tool separate the cylinder head and gasket and position the gasket on the block and remove the valve locks, retainers, from the block. with the stamped word "TOP" facing springs and valve stem oil deflectors. upward. Remove the valves one at a time Cleaning and Inspection CAUTION: Do not apply sealing and place them in a rack in the same Thoroughly clean the gasket surface of the cylinder head and block to re­ move all dirt and gasket cement. Re­ move the carbon deposits from the combustion chambers and the top of each piston. Use a straight edge and feeler gauge to check the flatness of the cylinder head and block mating sur­ faces. Out of flatness must not exceed . 001" over a 1" length,. 003" over a 6" length and. 008" over the entire length.

Installation

If the cylinder head is to be re­ placed and the original valves re-used, remove the valves and measure the FIGURE 16 — Torque Tightening Sequence Chart l-A-10 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement order as they were in the cylinder head.

Cleaning and Inspection

Clean all carbon buildup from the combustion chambers, valve ports, valve stems and heads. Clean all dirt and gasket cement from the cylinder head gasket surface. Inspect for cracks in the combustion chambers and valve ports. Inspect for cracks in the gasket surface at each coolant passage. Inspect for burned or cracked valve heads. Inspect for damaged valve stems.

Valve Refacing

Use a valve re-facing machine to reface the intake and exhaust valves 68125 to the specified angle. Replace any FIGURE 18 - Checking Valve Seat FIGURE 19 — Checking Valve Guide valve which is bent or warped. After Runout 1 Clearance refacing, at least I32" margin must re­ main or the valve must be replaced. Valve Stem to Guide Clearance Examples of correct and incorrect C-3427 . 030" valve refacing are shown in Figure 17. Valve stem to guide clearance may IMPORTANT: Valve guides must be be checked by two methods. reamed in steps, starting with the. 003" One method is to measure the valve O. S. reamer and progressing to the size stem diameter with a caliper microm­ required. eter midway between the valve head and tip and then select a pilot from a valve refacing kit which fits snugly Assembly in the valve guide bore. Thoroughly clean the valve stems Correct Valve Facing and the valve guide bores. No Margin NOTE: Make certain the valve stem and guide bore are thoroughly cleaned Install each valve in the same valve before measuring. guide from which it was removed. Install a new valve stem oil deflec­ The valve stem to guide clearance tor on each valve stem. can be determined by subtracting the Position each valve spring and re­ diameter of the valve stem from the tainer on the cylinder head and com­ Incorrect Valve Facing 70723 size of the pilot selected. press the valve spring with the com­ Another method is to use a dial in­ pressor tool. Install the valve locks FIGURE 17-Valve Refacing dicator to measure the lateral move­ and release the tool. ment of the valve stem with the valve Tap each valve spring from side to installed in its guide and off the valve The valve stem tip can be resurfaced side with a light hammer to be certain seat (Figure 19). and rechamfered when worn. How­ the spring is seated properly at the The valve guides are an integral ever, never remove more than. 010". cylinder head. part of the cylinder head and are not replaceable. Valve Seat Refacing HYDRAULIC VALVE TAPPETS Therefore, when the stem to guide Install a pilot of the correct size in clearance is excessive, the valve guides The hydraulic valve tappet consists the valve guide and reface the valve must be reamed to the next larger of a body, plunger, plunger return seat to the specified angle with a good size so that proper clearance can be spring, cap and lock ring (Fig. 20). dressed stone. Remove only enough obtained. Oversize service valves are The tappet operates in a guide metal to provide a smooth finish. available in. 003",. 015" and. 030" bore which has an oil passage drilled Narrowing stones should be used to sizes. into the adjoining main oil gallery. obtain the specified seat widths when The following oversize valve guide When the tappet is on the heel of required. reamers may be used. the cam lobe, the plunger return spring Control seat run-out to a maximum J-6042-1. 003" indexes with an oil hole undercut in of. 0025" (Fig. 18). C-3430 . 015" the plunger and allows the oil supply SIX CYLINDER ENGINE 1-A-ll 232-258 Cubic Inch Displacement

Noise Diagnosis

A loud clicking noise is usually the result of the plunger stuck below its operating position or a check valve held open. A light clicking noise at idle is usually the result of excessive "leak- down" caused by wear or slight leak­ age at the check valve and its seat. An intermittent noise is the result of dirt or chips stopping the check valve action or a lack of oil flow into the body. A general tappet noise is, in most cases, due to a lack of oil volume, pressure or cereation. A clicking noise, upon starting the engine, reducing in level and disap­ pearing after a short period of time is normal. This noise is due to a slight oil leak-down condition caused by valve spring pressure exerted on the Plunger tappets. Return Spring An individual noisy tappet can read­ ily be located by placing one end of a length of heater hose at the push rod end of the rocker arm and the FIGURE 20 - other end to the ear. Assembly Sequence (Typical) The valve tappets should be cleaned and serviced at time of engine over­ to be admitted through the tappet haul or whenever excessive noise exists. body. Oil under pressure flows into FIGURE 22 — Removing Valve Tappets the body through the check valve Removal and Disassembly with J-21884 assembly, maintaining the tappet fully charged. (Fig. 21). This cycle of opera­ Remove the cylinder head cover and The inspection should include check­ tion occurs when the tappet leaks off gasket, rocker arm and shaft assembly, ing for signs of scuffing on the barrel, some oil during the normal valve open­ push rods and the cylinder head and and face of the tappet. Each tappet ing events. Contact with the cam lobe gasket. face should be inspected for wear as causes tappet body movement, closing NOTE-. The push rods should be re­ shown in Figure 23. If the tappet face the check valve and transmitting "zero- tained in the same order as removed. is concave, the corresponding lobe on lash" movement of the push rod to the camshaft is worn and the replace­ open the intake or exhaust valve. Remove the tappets through the ment of the camshaft and tappets is push rod openings of the necessary. with Hydraulic Valve Tappet Remover If any components of a tappet as­ and Installer Tool J-21884 as shown sembly are noticeably worn or dam­ in Figure 22. aged, replace the entire assembly. IMPORTANT: The tappets and all After cleaning and inspection, the components must be retained in the tappet must be "leak-down" tested to same order as removed. insure its "zerolash" operating ability. Valve Tappet Test Oil J-5268 should Release the lock ring and remove the be used for this test. plunger cap, plunger assembly and Figure 24 illustrates Tool J-5790 plunger return spring from the tappet body. used to accurately test tappet "leak- down. " They may be tested by filling Cleaning and Inspection the body with Valve Tappet Test Oil J-5268, installing the plunger return Clean all components of the hydrau­ spring, plunger assembly, and plunger

Charging Cycle Leak Down Cycle lic tappet assembly in a good cleaning cap. Do not install lock ring for test. (Valve Closed) (Valve Open) solvent to remove all varnish or gum Place a. 312"-. 313" diameter ball deposits. bearing in the plunger cap. Place the FIGURE 21 - Hydraulic Tappet A visual inspection of each tappet push rod on the ball bearing. Operation Cycle assembly is required. Adjust the tester gauge on the l-A-12 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

Installation damper. Remove the vibration damper retain­ Dip each tappet assembly in Engine ing bolt and washers. Oil Supplement and use Hydraulic Use Vibration Damper Remover Tool Valve Tappet Remover and Installer J-21791 to remove the damper from Tool J-21884 to install the assemblies the crankshaft as shown in Figure 26. in the same bores from which they were removed. Install the push rods in the same order as removed. Install the rocker arm and shaft assembly and tighten the retaining bolts to the specified torque. Pour the remaining engine oil sup­ plement over the entire valve train mechanism.

IMPORTANT: The E. O. S. must remain in the engine for at least 1, 000 miles but need not be drained until the next scheduled oil change.

FIGURE 23 — Checking Tappet Face Install the cylinder head cover and gasket. for Concave Wear FIGURE 26 — Removing Vibration Damper Assembly with Tool J-21791 VIBRATION DAMPER

The vibration damper (Fig. 25) is Installation balanced independently and then re­ Align the key slot of the vibration balanced as part of the complete damper with the crankshaft key and crankshaft assembly. install the damper on the crankshaft. Install the vibration damper retain­ ing bolt and washers, tighten to the specified torque. If removed, install the accessory pulley and retaining cap screws, tighten the screws to the specified torque. Install the drive belt(s) and tighten FIGURE 24 - Testing Valve Tappet to the specified tension. "Leak-Down" with J-5790

TIMING CHAIN COVER start position and allow the weighted arm to "leak, down" the tappet. The timing chain cover is provided If the tappet leaks down rapidly or with a seal and oil slinger to prevent collapses immediately, it must be re­ FIGURE 25 — Vibration Damper oil leakage at the vibration damper placed with a complete new tappet Assembly hub (Fig. 27). assembly. A good tappet will take Do not attempt to duplicate original approximately 20-110 seconds to damper balance holes when installing "leak-down" with a 50 lb. load travel of. 125". a service replacement. The vibration damper is not repair- able and is serviced only as a complete Assembly and Testing assembly. After testing the tappets, install the A loose vibration damper or dam­ lock rings to those which have passed age to the damper cushions may be the test. Discard those which have misdiagnosed as engine bearing noise. failed the test and replace with new FIGURE 27 — Timing Chain Cover tappet assemblies. Removal

NOTE: Do not charge the tappet as­ Remove the drive belt(s). It is important that the timing chain semblies with engine oil as they will If so equipped, remove the three cover is properly aligned with the charge themselves within 3 to 8 minutes retaining cap screws and separate the crankshaft to prevent eventual damage of engine operation. accessory pulley from the vibration to the oil seal. The oil seal may be SIX CYLINDER ENGINE l-A-13 232-258 Cubic Inch Displacement replaced without removing the timing and remove the seal. Clean the timing Install the cover to block screws and chain cover. chain cover, oil pan and cylinder block oil pan to cover screws, tighten the gasket surfaces. screws to the specified torque. Removal Remove the crankshaft oil seal from Remove the cover aligning tool, the timing chain cover. place a new oil seal on the tool with Remove the drive belt(s), engine fan the seal lip facing the cover. Place a and hub assembly, accessory pulley Installation light film of "Perfect Seal" on the out­ (if so equipped) and vibration damper. side diameter of the seal. Insert the Apply "Perfect Seal" sealing com­ Remove the oil pan to timing chain draw screw from Tool J-9163 into the pound, or equivalent, to both sides of cover screws and the cover to block seal installing tool and press the seal a new timing cover gasket and position screws. into the cover until bottomed in seal the gasket on the cylinder block. Raise the timing chain cover just opening (Fig. 30). Remove the tools; Cut off the same amount from the high enough to detach the retaining apply a light film of engine oil on the end tabs of a new oil pan seal as was nibs of the oil pan neoprene seal from seal lip. Install the vibration damper cut off the original seal. Coat the end the bottom side of the cover. This must and tighten to the specified torque. be done to prevent pulling the seal tabs of the seal generously with "Per- If removed, install the accessory end tabs away from the tongues of the matex" No. 2 and install the seal to pulley. oil pan gaskets which would cause an the oil pan. Install the engine fan and hub as­ oil leak and necessitate removal of the Position the timing chain cover on sembly. oil pan to correct. the engine and place Timing Chain Install the drive belt(s) and tighten Remove the timing chain cover and Cover Alignment Tool and Seal In­ to the specified tension. gasket from the engine. staller J-22248 on the crankshaft and Use a sharp knife or single edge in the seal opening of the cover (Fig. Oil Seal Replacement razor blade to cut off the oil pan seal 29). end tabs flush with the front face of the Remove the drive belt(s), accessory cylinder block as shown in Figure 28 pulley (if so equipped) and the vibra­ tion damper. Use Timing Chain Cover Oil Seal Remover Tool J-9256 to remove the oil seal from the cover as shown in Figure 31. Place a new oil seal on Timing Chain Cover Alignment Tool and Seal Installer J-22248 with the seal lip facing the cover. Place a light film of "Perfect Seal" on the outside diameter of the seal. Insert the draw screw from Tool J-9163 into the seal installing tool and press the seal into the cover until bottomed in the seal opening. FIGURE 29 — Aligning Timing Chain Remove the tools; apply a light film FIGURE 28 — Cutting Oil Pan Front Cover of engine oil on the seal lip. Install the Seal l-A-14 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

vibration clamper and tighten to the CAMSHAFT AND BEARINGS specified torque. The camshaft is supported by four If removed, install the accessory pulley. steel-shelled, Babbitt-lined bearings which have been pressed into the Install the drive belt(s) and tighten block and line reamed. The camshaft to the specified tension. bearings are step bored, being larger at the front bearing than at the rear, TIMING CHAIN to permit easy removal and installa­ installation of the timting chain with tion of the camshaft. All camshaft the timing marks of the crankshaft and bearings are lubricated under pres­ camshaft sprockets properly aligned sure. assures correct valve timing. A worn NOTE; It is not advisable to replace timing chain will adversely affect valve camshaft bearings unless equipped with timing. If the timing chain deflects 4501? special removing, installing and reaming more than y2", it should be replaced. tools. FIGURE 32 - Place Marked Teeth Checking Valve Timing on Center Line When Installing Camshaft end play is maintained by Sprockets and Chain the load placed on the camshaft by Remove the spark plugs and the the oil pump and distributor drive cylinder head cover and gasket. shaft sprocket and camshaft sprocket gear. Rotate the crankshaft until No. 6 with the timing marks aligned as The helical cut of the gear holds the piston is at TDC on the compression shown in Figure 32. Install the assembly camshaft sprocket thrust face against . to the crankshaft and camshaft. Install the cylinder block face. Therefore, Turn the crankshaft slowly counter- the camshaft sprocket retaining bolt camshaft end play is zero during en­ clockwise (viewed from front) until No. and washer and tighten to the specified gine operation. 1 exhaust valve just begins to open. torque. To assure correct installation Note the distance between the timing of the timing chain, locate the timing Measuring Cam Lobe Lift mark on the vibration damper and the mark of the camshaft sprocket at TDC mark on the degree scale of the approximately the one o'clock position. Cam lift is a function of camshaft timing chain cover. This should place the of lobe dimensions. Turn the crankshaft slowly clockwise the crankshaft sprocket where it meshes Cam lift may be checked with a dial (viewed from the front) past TDC posi­ with the chain (Fig. 33). Count the indicator. tion until No. 1 intake valve just be­ number of pins between the timing To check cam lift, remove the cylin­ gins to open. Note the distance be­ mark of both sprockets. There should der head cover and gasket, rocker tween the timing mark on the vibration be 15 pins. arm assembly and spark plugs. Install damper and the TDC mark on the de­ a dial indicator on the end of the push gree scale of the timing chain cover. rod as shown in Figure 34. A piece of If the valve timing is correct, the rubber tubing may be used to secure two distances will be equal. the dial indicator plunger to the push rod. Removal Rotate crankshaft until the cam lobe base circle (push rod down) is under Remove the drive belt(s), engine fan the valve tappet. Set the dial indica­ and hub assembly, accessory pulley (if tor to zero and rotate the crankshaft so equipped), vibration damper and to a point where maximum upward timing chain cover. Remove the oil movement of the push rod occurs. seal from the timing chain cover. Read the travel at the dial indicator. Remove the camshaft sprocket re­ An excess of minus. 006" from the spec­ taining bolt and washer. ified dimensions indicates a defective Rotate the crankshaft until the "0" cam. timing mark on the crankshaft sprocket 65020 is closest to and in a centerline with the timing pointer of the camshaft sprocket FIGURE 33 — Correct Timing Chain Removal as shown in Figure 32. Installation Drain the cooling system and remove Remove the crankshaft sprocket, the radiator. If equipped with air con­ camshaft sprocket and timing chain as Install the timing chain cover and a ditioning, remove the condenser and an assembly. Disassemble the chain new oil seal. Install the vibration receiver assembly as a charged unit. and sprockets. damper, accessory pulley (if so Refer to the "AIR CONDITIONING" Installation equipped), engine fan and hub as­ section for detailed procedure. sembly and the drive belt(s). Tighten Remove the cylinder head cover and Assemble the timing chain, crank- the belt(s) to the specified tension. gasket, rocker arm and shaft assembly, SIX CYLINDER ENGINE l-A-15 232-258 Cubic Inch Displacement

Inspect the distributor drive gear for OIL PAN damage or excessive wear. Inspect each cam lobe and the Removal matching hydraulic valve tappet for Raise the vehicle and drain the wear. If the face of the tappet(s) is engine oil. worn concave, the matching camshaft Remove the starter motor. lobe(s) is also worn, both the camshaft On CJ-5/CJ-6 and Commando, and the tappet(s) must be replaced. place a jack under the transmission bell housing. Disconnect the engine right support cushion bracket from the Installation block and raise the engine to allow sufficient clearance for oil pan re­ Lubricate the entire camshaft gener­ moval. ously with Engine Oil Supplement and Remove the oil pan. install carefully into the engine block. Remove the oil pan front and rear Assemble the timing chain, crank­ neoprene oil seals and the side gas­ shaft sprocket and camshaft sprocket kets. Thoroughly clean the gasket sur­ with the timing marks aligned as shown faces of the oil pan and engine block. in Figure 32. Install the assembly to Remove all sludge and dirt from the the engine. oil pan . Install the timing chain cover and a new oil seal. Install the vibration damper. If re­ Installation moved, install the accessory pulley. Install a new oil pan front seal to Install the engine fan and hub as­ the timing chain cover and apply a sembly and the drive belt(s). Tighten generous amount of "Permatex" No. 2, the belt(s) to the specified tension. FIGURE 34 - Installation of Dial or equivalent, to the end tabs. Install the fuel pump. Indicator for Checking Cam Lobe Lift Cement new oil pan side gaskets Rotate the crankshaft until No. 1 into position on the engine block and piston is at TDC position on the com­ apply a generous amount of "Perma­ push rods, cylinder head and gasket, pression stroke. Install the distributor tex" No. 2, or equivalent, to the gasket and hydraulic valve tappets. so that the rotor is aligned with the ends. No. 1 terminal of the cap when fully Coat the inside curved surface of a NOTE: The push rods and tappets seated on the block. Install the distri­ new oil pan rear seal with soap and should be retained in the same order butor cap and spark plug wires. apply a generous amount of "Perma­ as removed. Install the hydraulic valve tappets, tex" No. 2, or equivalent, to the gas­ Remove the drive belt(s), engine fan cylinder head and gasket, push rods, ket contacting surface of the seal end and hub assembly, accessory pulley (if rocker arm and shaft assembly, and tabs. cylinder head cover and gasket. so equipped), vibration damper and Install the seal in the recess of the timing chain cover. Remove the oil seal IMPORTANT: The hydraulic valve tap­ rear main bearing cap making certain from the timing chain cover. pets and all valve train components it is fully seated. Remove the fuel pump and distribu­ should be lubricated with Engine Oil Apply engine oil to the oil pan tor assembly (including spark plug Supplement during installation. The contacting surface of the front and rear wires). E. O. S. must remain in the engine for at oil pan seals. Rotate the crankshaft until the "0" least 1, 000 miles but need not be Install the oil pan and tighten the timing mark of the crankshaft sprocket drained until the next scheduled oil drain plug securely. is closest to and in a centerline with change. If disconnected, lower the engine the timing pointer of the camshaft and connect the right support cushion sprocket as shown in Figure 32. If removed, install the air condition­ bracket to the block. Remove the jack. Remove the crankshaft sprocket, ing condenser and receiver assembly. Install the starter motor. camshaft sprocket and timing chain as Refer to the "AIR CONDITIONING" Lower the vehicle and use new oil an assembly. section for procedure to purge the to fill the crankcase to the specified Remove the front bumper or grille compressor of air. level. as required and remove the camshaft. CAUTION: Both service valves must OIL PUMP be open before the air conditioning Inspection system is operated. Removal

Inspect the camshaft bearing jour­ Install the radiator and fill the cool­ Drain the engine oil and remove the nals for an uneven wear pattern or ing system to the specified level. oil pan. rough finish. Either condition will ne­ If removed, install the front bumper Remove the oil pump retaining cessitate camshaft replacement. or grille. screws and separate the oil pump and 1-A-16 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement gasket from the engine block. Install the idler shaft, idler gear and drive gear assembly. CAUTION: Do not disturb the position of the oil pick-up tube and screen as­ IMPORTANT: To ensure self-priming sembly in the pump body. If the tube is of the oil pump, the pump must be moved within the pump body, a new filled with "Petrolatum" prior to the in­ assembly must be installed to assure an stallation of the oil pump cover. (Do air tight seal. not use grease of any type. )

Install the pump cover and new Disassembly and Inspection gasket. Tighten the retaining screws to Remove the cover retaining screws the specified torque. and separate the cover and gasket NOTE: Check for free operation prior from the pump body. to installing the oil pump to the engine. Measure the gear end clearance by placing a straight edge across the Install the oil pump and a new gas­ gears and pump body. Select a feeler ket to the engine block. Tighten the gauge which will fit snugly but freely retaining screws to the specified torque. between the straight edge and the Install the oil pan using new gaskets pump body (Fig. 35). Refer to the and seals. Use new oil to fill the Specifications pages for the correct crank case to the specified level. clearance. FIGURE 36 — Measuring Oil Pump Gear to Body Clearance REAR MAIN BEARING OIL SEAL IMPORTANT: The oil pick-up tube The rear main bearing crankshaft must be moved to allow removal of the seal consists of a two piece neoprene relief valve; therefore, the pick-up tube single lip seal to effectively seal the assembly must be replaced upon instal­ rear of the crankshaft. Correct instal­ lation. lation of the seal will assure leak free engine operation (Fig. 38). Assembly and Installation

If removed, install the oil pressure relief valve, spring, retainer and cotter pin. If the position of the pick-up tube in the pump body has been disturbed, a new pick-up tube assembly must be installed. FIGURE 35 — Measuring Oil Pump Gear End Clearance Prior to installing the new assembly, place a light film of "Permatex" No. 2, If the gear end clearance is less than or equivalent, around the tube at the specified, replace the oil pump as­ joint. Using Tool J-21882 as shown in FIGURE 38 - Rear Main Oil Seal sembly. Figure 37, drive the tube into the body and Cap Installation Measure the gear to body clearance making sure that the alignment of the by inserting a feeler gauge between support bracket is correct during the the gear tooth and the pump body entire installing operation. Removal and Installation inner wall directly opposite the point of gear mesh. Select a feeler gauge Drain the engine oil and remove the which fits snugly but freely (Fig. 36). oil pan. Rotate the gears to check each tooth Remove the oil pan front and rear in this manner. Refer to the Specifica­ neoprene oil seals. Remove the oil pan tions pages for the correct clearance. side gaskets. Thoroughly clean the If the gear to body clearance is gasket surfaces of the oil pan and more than specified, replace the idler engine block. Remove all sludge and gear, idler shaft and drive gear assem­ dirt from the oil pan sump. bly. Remove the rear main bearing cap. If required, the oil pressure relief Remove and discard the lower seal. valve may be removed from the pump IMPORTANT: To assure leak free op- body for cleaning. Remove the cotter eration, the upper and lower seal halves pin and slide the spring retainer, must be replaced in pairs. spring and relief valve out of the pump body. FIGURE 37 - Installing Pick-up Tube Clean the main bearing cap SIX CYLINDER ENGINE l-A-17 232-258 Cubic Inch Displacement thoroughly to remove all sealer. alloy precision type. of the connecting rod. Loosen all remaining main bearing Each bearing is selective fit to its NOTE: Do not mix bearing caps. cap screws. respective journal to obtain the de­ Each connecting rod and its matching With a brass drift and hammer, tap sired operating clearance. In produc­ cop is stamped with the cylinder num­ the upper seal until sufficient seal is tion the select fit is obtained by using ber on a machined surface which faces protruding to permit pulling the seal various sized color coded bearing in­ the camshaft side of the engine block. out completely. Wipe the seal surface serts as shown in the bearing fitting of the crankshaft clean; then oil chart. Inspect the bearing inserts for ab­ lightly. When required, different sized up­ normal wear or damage. Bearing in­ Coat the block contacting surface of per and lower bearing inserts may be serts with either condition should be the new upper seal with soap, and the used as a pair; therefore, a standard replaced. lip of the seal with engine oil. Install size upper insert is sometimes used in Wipe the connecting rod journals the upper seal into the engine block. combination with a. 001" undersize clean and use a micrometer to check (U. S. ) lower insert. for an out of round condition. Refer to CAUTION: The lip of the seal must Service replacement bearing inserts specifications. If any rod journal is face to the front of the engine. are available as pairs in the following beyond specifications, it must be re­ Coat both sides of the new lower sizes: standard,. 001" U. S.,. 002" U. S., conditioned and fitted with new under­ seal end tabs with "Permatex" No. 2 . 010" U. S. and. 012" U. S. The size is size bearing inserts. or equivalent, being careful not to stamped on the back of the inserts. apply sealer to the lip of the seal. The bearing fitting chart may be Measuring Bearing Clearance Coat the outer curved surface of utilized to select the bearing inserts re- With Plastigage the lower seal with soap and the lip quired to obtain the specified bearing of the seal with engine oil. Install the clearance. Wipe the bearing inserts and rod seal into the cap recess and seat it firmly. CONNECTING ROD BEARING FITTING CHART Place "Permatex" No. 2, or equiva­ lent, on both chamfered edges of the Diameter Of Upper Color Lower Color rear main bearing cap. Install the rear Rod Journal Bearing Code Bearing Code main bearing cap and inserts. Tighten 2. 0955"-2. 0948" Standard Yellow Standard Yellow all main bearing cap screws to the 2. 0948"-2. 0941" Standard Yellow . 001 "U. S. Black specified torque. Install a new oil pan front seal to 2. 0941"-2. 0934" . 001" U. S. Black . 001" U. S. Black the timing chain cover and apply a 2. 0855"-2. 0848" . 010" U. S. Red . 010" U. S. Red generous amount of "Permatex" No. 2, or equivalent, to the end tabs. Cement new oil pan side gaskets It may be necessary, in some in­ journal clean. Place a strip of Plasti- into position on the engine block and stances, to use different sized upper gage across the full width of the lower apply a generous amount of "Perma­ and lower inserts to reduce clearance insert at the center of the bearing cap. tex" No. 2, or equivalent, to the gasket by. 0005" (54 thousandth"). The bear­ Install the bearing cap to the con­ ends. ing insert nearest to standard should necting rod and tighten the retaining Coat the inside curved surface of a always be installed in the upper nuts to the specified torque. new oil pan rear seal with soap and location. Remove the bearing cap and deter­ apply a generous amount of "Perma­ mine the amount of clearance by CAUTION: Never use bearing inserts tex" No. 2, or equivalent, to the gasket measuring the width of the compressed with greater than. 001" difference in contacting surface of the seal end Plastigage with the scale furnished as size in pairs. tabs. shown in Figure 39. Install the seal in the recess of the Example rear main bearing cap making certain Correct Incorrect it is fully seated. Upper — Std. Upper — Std. Apply engine oil to the oil pan Lower -. 001" U. S. Lower -. 002" U. S. contacting surface of the front and rear oil pan seals. Removal and Inspection Install the oil pan and tighten the drain plug securely. Drain the engine oil and remove the FIGURE 39 — Checking Bearing Use new oil to fill the crankcase to oil pan. Clearance with Plastigage the specified level. Rotate the crankshaft as required to position two pistons at a time at the Measuring Connecting Rod bottom of their stroke. CONNECTING ROD BEARINGS Journal With A Micrometer Remove the bearing caps and upper The connecting rod bearings are and lower inserts. The upper insert can Wipe the connecting rod journal steel-backed, sintered copper, lead be readily removed by spinning it out clean. l-A-18 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

Use a micrometer, measure the maxi­ with an inside micrometer or telescope Pistons are fitted to their respective mum diameter of the rod journal. gauge from the top to the bottom of bores by measuring the inside diam­ Compare the reading obtained with the cylinders for taper. Check for an eter of the cylinder bore and the the journal diameters listed in the bear­ out of round condition by measuring diameter of the piston. ing fitting chart and select the inserts across the cylinder bores at two points; Measure the cylinder bore inside 5 required to obtain the specified bear­ parallel to the crankshaft and per­ diameter at a point 2 /j6" below the ing clearance. pendicular to the crankshaft. top of the bore. If cylinder taper does not exceed Pistons are cam ground and, there­ Installation . 005" and out of round does not fore, must be measured at right angles exceed. 003", the cylinder bore may to the piston pin at the center line of Lubricate the bearing surface of be trued by honing. pin as shown in Figure 41. each insert with clean engine oil. In­ If the cylinder taper or out of stall the bearing inserts, cap and re­ round condition exceeds these limits, taining nuts. Tighten to the specified the cylinder must be bored and then torque. honed for an oversize piston. CAUTION: Care must be exercised When finish honing the cylinder when rotating the crankshaft with bear­ bores, move the hone up and down at ing caps removed. Be sure the connect­ sufficient speed to produce a uniform ing rod bolts do not accidentally come cross hatch pattern on the cylinder in contact with the rod journals and walls. scratch the finish. Bearing failure would Prior to fitting pistons, the cylinder result. bores should be scrubbed clean with a hot water and detergent solution. Install the oil pan using new gaskets Cover the connecting rod journals with and seals. Tighten the drain plug se­ clean cloths during the cleaning opera­ curely. tion. Use new engine oil to fill the crank- After cleaning, apply light engine case to the specified level. oil to the cylinder walls and then wipe with a clean lint free cloth. CONNECTING ROD AND FIGURE 41 — Piston Measurements PISTON ASSEMBLIES Pistons The difference between cylinder Aluminum alloy "Autothermic" pis­ Removal bore diameter and piston diameter tons, steel reinforced for strength and Remove the cylinder head cover and dimensions is the piston to bore clear­ controlled expansion are used. The gasket, rocker arm and shaft assembly, ance. push rods and the cylinder head and ring belt area provides for three pis­ ton rings, two compression and one oil gasket. Piston Rings Position the pistons one at a time control ring above the piston pin. near the bottom of their stroke and The piston pin boss is "offset" from Carbon must be cleaned from all use a ridge reamer to remove any the piston center line to place it ring grooves. The oil drain openings ridge from the top end of the cylinder nearer the thrust side of the piston. in the oil ring grooves and pin boss walls. To ensure correct installation of the must be cleared. Care must be exer­ Drain the engine oil and remove piston in the bore, a notch is cast cised not to remove metal from the the oil pan. into the top perimeter of the piston grooves since this will change their Remove the connecting rod bearing head. The notch must face forward as depth; nor from the lands since this caps and inserts and retain in the same shown in Figure 40. will change the ring groove clearance order as removed.

NOTE: Connecting rods and caps are stamped with the number of the cylinder to which they were assembled.

Remove the connecting rod and pis­ ton assemblies through the top of the cylinder bores being careful that the connecting rod bolts do not scratch the connecting rod journals or cylinder walls.

Cylinder Bore Conditioning

Inspect the cylinder bores for scor­ ing, taper, and out of round. Check FIGURE 40 — Pistons Correctly Positioned in Bores SIX CYLINDER ENGINE l-A-19 232-258 Cubic Inch Displacement

and destroy ring to land seating. upon cleanliness during the honing Side clearance between land and operation or when handling parts. The compression rings should be as listed engine bearings and lubrication sys­ on the Specifications pages. tem must be protected from abrasives. Roll the ring around the groove in Rigid type hones are not to be used which it is to operate. It must fit freely to remove cylinder glaze as there is at all points (Fig. 42). always a slight amount of taper in cylinder walls after the engine has been in service. After removing the cylinder glaze, install the rings on the pistons. Install the oil control rings first by following the sequence shown in Figure 44. Com­ pression rings are marked to designate top of ring. Typical compression ring markings are shown in Figure 45. FIGURE 46 — Installing Compression Rings on Piston Using Tool J-8028

FIGURE 42 - Checking Ring Side Clearance 70726

Piston ring gap or joint clearance is Cylinder measured at the bottom of the cylinder Number near the end of the ring travel area. Squirt Hole To square the ring in the bore for checking joint clearance, place the ring in the bore, then, with an inverted piston, push the ring down near the lower end of ring travel area (Fig. 43). FIGURE 47 — Connecting Rod FIGURE 44 - Oil Control Ring Numbering and Squirt Hole Location Installation

blies to ensure true operation in the cylinder bore. Misaligned rods will cause uneven FIGURE 45 — Typical Piston Ring piston and ring wear which will result Markings in oil consumption. The connecting rod Rings must be installed on the pis­ should be inspected for a twisted or tons with a ring installing tool to pre­ bent condition. vent distortion and ring breakage Assemble the connecting rods to the (Fig. 46). pistons with the notch on the pistons facing to the front of the engine and the numbered side of the rods facing Connecting Rods And the camshaft. FIGURE 43 — Checking Ring Gap Piston Pins Clearance The piston pins are a press fit into The connecting rods and caps are the connecting rod, thus requiring no When other than standard ring sizes stamped with the cylinder numbers in locking device. are used, rings should be individually which they were assembled. Remove the piston pin with Piston Pin fitted to their respective bores. The numbers are on the same ma­ Remover J-21872 and an arbor press. Removal of glaze from the cylinder chined surface as the squirt holes (Fig. Place the piston on the remover wall for quicker ring seating can be 47). support J-21872-1 so that the pin will accomplished by various methods. The numbered sides and the squirt enter the support when pressed out When an expanding type hone is holes must face the camshaft. with the piloted driver J-21872-3 (Fig. used, do not use more than ten strokes Whenever new rings are installed 48). (each stroke down and return) to re­ or piston pins are replaced, it is To install the piston pin, place the condition a cylinder wall. necessary to check the alignment of piston pin pilot in the support and in­ Successful ring installation depends the connecting rod and piston assem- sert the piston and connecting rod. This l-A-20 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

#2 compression ring gap. The oil con­ are available as pairs in the following trol ring gaps are to be installed 90° sizes: standard,. 001" U. S.,. 002" U. S., from the spacer gap with at least 30° . 010" U. S. and 012" U. S. The size between each ring gap. is stamped on the back of the inserts. Lubricate the piston and ring sur­ The bearing fitting chart may be faces with clean engine oil. utilized to select the bearing inserts re­ Use Piston Ring Compressor Tool quired to obtain the specified bearing C-385 to install the connecting rod clearance. and piston assemblies through the top It may be necessary, in some in­ of the cylinder bores being careful stances, to use different sized upper that the connecting rod bolts do not and lower inserts to reduce clearance scratch the connecting rod journals or by. 0005" (1/2 thousandth"). The bear­ cylinder walls. ing insert nearest to standard should always be installed in the upper lo­ NOTE: Lengths of rubber hose slipped cation. over the connecting rod bolts will afford protection during installation. CAUTION: Never use bearing inserts with greater than. 001" difference in Install the connecting rod bearing size in pairs. caps and inserts in the same order as removed. Tighten the retaining nuts to Example: the specified torque. Install the engine oil pan using new Correct Incorrect gaskets and seals. Tighten the drain Upper — Std. Upper — Std. 65103 plug securely. Lower -. 001" U. S. Lower -. 002" U. S. FIGURE 48 — Removing or Installing Install the cylinder head and new Piston Pin gasket, push rods, rocker arm and shaft Removal and Inspection assembly and cylinder head cover and Drain the engine oil and remove the aligns the piston and connecting rod gasket. pan. piston pin bores. Press the piston pin Use new oil to fill the crankcase to Remove one main bearing cap and into the connecting rod and piston as­ the specified level. insert. sembly until the lower pilot enters the Inspect the bearing insert for ab­ support and the index mark on the CRANKSHAFT MAIN BEARINGS normal wear or damage. If either con­ pilot is located at the lower edge of The main bearings are steelbacked, dition exists, both upper and lower the gauge window of support sintered copper, lead alloy precision inserts must be replaced. Refer to J-21872-1. At this point, the connect­ type. "Measuring Bearing Clearance With ing rod is centered on the piston pin. 1 Each bearing is selective fit to its Plastigage" to select the bearing in­ A plus or minus /32" is allowed for respective journal to obtain the desired serts required to obtain the specified centering the piston pin to connecting operating clearance. In production the bearing clearance. rod. select fit is obtained by using various Inspect the crankshaft main journal. When fitting the pin, with all parts sized color coded bearing inserts as If it is damaged, it must be either re­ dry and free of nicks and burrs, shown in the bearing fitting chart. conditioned or replaced. Refer to the pin must not support its weight in a When required, different sized upper "Crankshaft. " vertical position over its entire length and lower bearing inserts may be used Remove the upper insert by loosen­ in either of the bores. as a pair; therefore, a standard size ing all of the other bearing caps and l CAUTION: The piston pins must be a upper insert is sometimes used in com­ inserting a small pin about /2" long tight press fit (2000 lb. ) into the con­ bination with a. 001" undersize (U. S. ) in the crankshaft oil hole. The head of necting rod. lower insert. this pin should be large enough so that Service replacement bearing inserts it will not fall into the oil hole, yet Installation

After thoroughly cleaning the cylin­ der bores, apply a light film of clean CRANKSHAFT BEARING FITTING CHART engine oil to the bores with a clean lint free cloth. Diameter Of Upper Color Lower Color Prior to installing the connecting rod Main Journal Bearing Code Bearing Code and piston assemblies into the engine, 2. 5001 "-2. 4996" Standard Yellow Standard Yellow arrange the piston ring gaps so that 2. 4996"-2. 4991" Standard Yellow . 001" U. S. Black the #1 compression ring gap is 180° 2. 4991 "-2. 4986" . 001" U. S. Black . 001" U. S. Black from the #2 compression ring gap and the oil control ring spacer ex­ 2. 4986"-2. 4981" . 001" U. S. Black . 002" U. S. Green pander gap is at least 90° from the 2. 4901 "-2. 4896" . 010" U. S. Red . 010" U. S. Red SIX CYLINDER ENGINE l-A-21 232-258 Cubic Inch Displacement

thinner than the thickness of the bear­ Use new engine oil to fill the crank- ing. case to the specified level. With the pin in place, rotate the shaft so that the upper bearing insert CRANKSHAFT will rotate in the direction of its lo­ cating tongue. The crankshaft is counterweighted Remove and inspect the remaining and balanced independently. The 232 bearings one at a time in the same CID crankshaft has eight counter- manner. weights and the 258 CID crankshaft has twelve counterweights. Both have Measuring Bearing Clearance seven main bearings and six connect­ With Plastigage ing rod journals. An oil slinger is provided at the Support the weight of the crankshaft rear main journal inboard of the rear with a jack placed under the counter­ oil seal. weight which is adjacent to the main The component parts of the crank­ bearing being checked. shaft assembly are individually bal­ anced; then the complete assembly is IMPORTANT-. Check clearance of only balanced as a unit. one bearing at a time. All other bear­ ings must remain tightened. IMPORTANT: On automatic transmis­ sion equipped engines, the torque con­ FIGURE 50 - Checking Crankshaft Remove the main bearing cap and verter and converter flexplate must be End Play insert. Wipe the insert and the ex­ marked prior to removal and installed posed portion of the crankshaft journal in this position upon assembly. sembly consists of engine block, piston clean. and rod assemblies, crankshaft, cam- Place a strip of Plastigage across the Service replacement dampers, crank­ shaft, timing gears and chain. full width of the bearing insert. Install shafts, , torque converters, Installation includes transfer of com­ the bearing cap and tighten the retain­ and clutch components are balanced ponent parts from the original engine ing bolts to the specified torque. individually and, therefore, may be including cleaning and torque tighten­ Remove the bearing cap and deter­ replaced as required without rebalanc­ ing as required. mine the amount of clearance by ing the complete assembly. measuring the width of the compressed IMPORTANT: Whenever installing a Plastigage with the scale furnished as Replacement short engine assembly, always install a shown in Figure 49. new engine oil pump pick-up tube and If the crankshaft is damaged to the screen assembly. extent that reconditioning is not feas­ ible, it must be replaced. The engine FLYWHEEL AND STARTER must be removed from the vehicle for RING GEAR ASSEMBLY crankshaft replacement. The starter ring gear can be re­ Checking End Play placed separately only on vehicles with manual transmission. The starter ring The crankshaft end play is con­ gear is welded to and balanced as 60291 trolled at the No. 3 main bearing in­ part of the converter flexplate on ve­ FIGURE 49 - Checking Main Bearing sert which is flanged for this purpose. hicles with automatic transmission. Clearance With Plastigage To check this clearance, attach a To remove, place the flywheel on an dial indicator to the crankcase and arbor press with steel blocks equally pry the shaft fore and aft with a spaced under the gear and press the Installation screw driver (Fig. 50). flywheel through. The ring gear can Lubricate the bearing surface of The crankshaft end play should be also be removed by breaking it with a each insert with clean engine oil. as listed on the Specifications pages. chisel. Loosen all main bearing caps and To install a new starter ring gear, IMPORTANT: When replacing the install the main bearing upper insert(s). apply heat to expand the inside diam­ thrust bearings, it is recommended to Install the main bearing cap(s) and eter so that it can be pressed over the pry the crankshaft fore end aft to align lower insert(s). Tighten the retaining flywheel. the thrust faces of the bearings. bolts evenly to the specified torque. On manual transmission equipped After installation, turn the crank­ SHORT ENGINE ASSEMBLY vehicles, the flywheel is balanced as shaft by hand to check for free opera­ an individual component and also as tion. A service replacement short engine part of the crankshaft assembly. Install the oil pan using new gaskets assembly may be installed whenever Do not attempt to duplicate original and seals. Tighten the drain plug the original engine block is damaged flywheel balance holes when installing securely. beyond repair. The short engine as- a service replacement. l-A-22 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

Core Hole Plugs (Coolant)

Front

FIGURE 51 - Rear Camshaft and Oil Gallery Plugs FIGURE 52 - Core Hole Plug Location SIX CYLINDER ENGINE SPECIFICATIONS 232 CID 258 CID Type - OHV 6 Cyl. • Bore Stroke Firing Order Displacement Compression Ratio Net Horsepower Net Torque Taxable Horsepower Fuel Cylinder Head and Block Flatness

VALVES Valve Arrangement (Front to Rear) Valve Stem Diameter Valve Length Valve Guide I. D. (Integral) Stem to Guide Clearance Intake Valve Face Angle Intake Valve Seat Angle Intake Valve Seat Width Exhaust Valve Face Angle Exhaust Valve Seat Angle Exhaust Valve Seat Width Valve Seat Run-out

VALVE SPRING TENSION (LBS. ) Closed Open

INTAKE VALVE TIMING Opens Closes

EXHAUST VALVE TIMING Opens Closes (California) Closes (Nationwide) Valve Opening Overlap (California) Valve Opening Overlap (Nationwide)

CAMSHAFT Cam Lobe Lift SIX CYLINDER ENGINE l-A-23 232-258 Cubic Inch Displacement

End Play Bearing Clearance Intake Duration Exhaust Duration (California) Exhaust Duration (Nationwide) Base Circle Run-Out Tappet Clearance

PISTONS AND RINGS Pistons to Bore Clearance (Right Angle to Center Line of Piston Pin) Piston Ring Gap Clearance Top and Center (Compression) Bottom (Oil Control) Piston Ring Side Clearance #1 Compression #2 Compression Oil Control Piston Pin to Connecting Rod Piston Pin to Piston

CRANKSHAFT AND BEARINGS Main Bearing Journal Diameter Main Bearing Journal Width

Main Bearing Clearance Crankshaft End Play Connecting Rod Journal Diameter Connecting Rod Journal Width Connecting Rod Bearing Clearance Connecting Rod Side Clearance Connecting Rod Journal Out of Round

OIL PUMP AND LUBRICATING SYSTEM Oil Pump Type Normal Operating Pressure @ 600 RPM @ 1600 RPM or Higher Oil Pressure Relief Maximum Gear to Body Clearance Gear End Clearance (Cover and Gasket Removed) Oil Filter Engine Oil Capacity

TORQUE SPECIFICATIONS Cylinder Head Cover Screws 45-55 In. Lbs. (Torque Values given in Foot Pounds Crankshaft Pulley to Damper 20-25 Unless Otherwise Specified) Clutch Housing Spacer to Block Screw 10-15 Adjusting Strap and Water Pump to Stud. 18-25 Clutch or Bell Housing Alternator Bracket Bolt 18-35 Top 25-30 Alternator to Bracket Nut 30-35 Bottom 40-45 Camshaft Sprocket Screw 45-55 Distributor Clamp Bolt 10-15 Carburetor Hold-Down Nuts 12-15 Distributor Bracket Screw 10-15 Connecting Rod Nuts 26-30 Exhaust Manifold Bolts 20-25 Cylinder Head Cap Screws 80-85 Exhaust Pipe to Manifold Nuts 20-25 l-A-24 SIX CYLINDER ENGINE 232-258 Cubic Inch Displacement

Fan and Spacer to Pulley Hub Bolt 15-25 Front Insulator to Frame Bracket Nut 25-30 Flex Plate to Converter 270 In. Lbs. Rear Insulator to Transmission Bolt 30-35 Flex Plate to Crankshaft 100-110 Insulator to Crossmember Locknut 25-30 Flywheel to Crankshaft Bolt 100-110 Insulator to Transmission 30-35 Front Cover to Block Screw 4-6 Rear Insulator to Crossmember Hex Nut 30-35 Fuel Pump Screws 15-17 Torque Reaction Bracket 25-30 Fuel Pump Clip to Oil Pan Bolt 5-8 Oil Pan Screws l/4"-20. 5-8 Fuel Pump Clip to T/C Cover Bolt 5-8 5/16"-18. 10-12 Ground Strap and Alternator Bracket 18-35 Rocker Arm Assy, to Head - Bolt 20-23 Ignition Coil Bolt 18-25 Spark Plugs 25-30 Intake Manifold to Head Bolt 20-25 Solenoid to Bracket Nut 18-25 Main Bearing Cap Screws 75-85 Starter Nut 30-35 Oil Pump; T. C. S. Solenoid Bracket and Accelerator Cable Cover to Body Bolt 5-8 Bracket to Intake Manifold Bolt 18-25 Pump to Block Bolt 10-12 Timing Chain Cover Bolt 5-8 Mounting and Connecting Parts: Thermostat Housing 10-15 Engine Mounting Brackets to Engine Bolt 25-30 Vibration Damper Screw 50-60 Bracket to Plate Bracket to Crossmember Nut 30-50 Water Pump to Block Bolt 10-15

• J-22248 Timing Chain Cover Alignment Tool and Seal Installer

J-21832 Oil Pump Inlet Tube Installer

J-21872 Piston Pin Remover J-5790 and Installer Hydraulic Valve Lifter Tester

J-21931 Valve Spring Remover and Installer

J-22700 Oil Filter Wrench

J-5959-4 J-21791 C-647 "C" Clamp and Vibration Damper Valve and Clutch Rod Extension Remover Spring Tester 69009

FIGURE 53 - Engine Tools