Timing, Synchronizing & Adjusting

ELECTRICAL 2 C

28245

TIMING, SYNCHRONIZING & ADJUSTING Table of Contents Page Timing/Synchronizing/ Adjusting...... 2C-1 Specifications...... 2C-1 Special Tools...... 2C-1 Adjustments...... 2C-2 Timing Pointer Adjustment...... 2C-2 Carburetor Synchronization...... 2C-2 Carburetor/Oil Pump Synchronization...... 2C-3 Timing Adjustments...... 2C-4 Maximum Timing Adjustment...... 2C-4 Primary Pickup Timing Adjustment...... 2C-5 Idle Speed Adjustment...... 2C-5

2C-0 - ELECTRICAL 90-852396 MAY 1996 Timing/Synchronizing/ Timing Light 91-99379 Adjusting

Specifications

Sport Jet 175XR2 Full Throttle RPM Range 5000-5500 Idle RPM 1000 - 1100 Maximum Timing: @ Cranking Speed 22° BTDC @ 5000 RPM 20° BTDC Idle Speed/Pickup Timing 0° "2° ATDC Spark Plug NGK-BU8H Firing Order 1-2-3-4-5-6

Special Tools Remote Starter Switch 91-52024A1

Dial Indicator 91-58222A1

90-852396 MAY 1996 ELECTRICAL - 2C-1 Adjustments 5. Remove dial indicator from cylinder.

TIMING POINTER ADJUSTMENT CARBURETOR SYNCHRONIZATION 1. Loosen 3 carburetor synchronization screws (a) ! WARNING to allow shutter plates to close completely. Engine could start when turning flywheel to 2. Position throttle lever so that idle stop screw is check timing pointer adjustment. Remove all against idle stop and move roller arm until roller spark plugs from engine to prevent engine from lightly touches throttle cam (b). Adjust idle stop starting. screw (c) on throttle arm to align mark (d) on throttle cam with center of roller. Without moving 1. Remove all spark plugs and install Dial Indicator roller from this position, retighten carburetor syn- (91-58222A1 ) into No. 1 cylinder (top cylinder, chronization screws. starboard bank).

28244 55087 2. Turn flywheel in a clockwise direction until No. 1 b piston is at top dead center (TDC). Set dial indicator at “O” (zero) and tighten indicator set screw. c 3. Turn flywheel counterclockwise until dial indicator needle is approximately 1/4-turn beyond .462 d in., then turn flywheel clockwise so that dial indicator reads .462 in. (11.7mm ) exactly. 4. Reposition timing pointer (a) “if necessary” so that timing pointer is aligned with .462 in. mark on timing decal. Retighten pointer attaching screws (b). a - Carburetor Synchronization Screws b - Throttle Cam c - Idle Stop Screw d - Alignment Mark b b 3. Verify throttle shutter plates open and close si- multaneously during throttle lever operation. Readjust if necessary.

28245 a - Timing Pointer b - Pointer Attaching Screws

2C-2 - ELECTRICAL 90-852396 MAY 1996 4. Move throttle lever to wide-open-throttle (W.O.T.) CARBURETOR/OIL PUMP SYNCHRONIZATION position and adjust full throttle stop screw (a) to 1. When carburetor linkage is at idle position, align- allow full throttle shutter opening at W.O.T. Verify ment mark (a) on oil injection arm should be that throttle shutters do not act as a throttle stop. in-line with mark on casting (b) as shown. If nec- Allow .010 in. - .015 in. (.25mm - .38mm) clear- essary, adjust link rod (c). ance between throttle shaft arm(b) and stop (c) at W.O.T. Retighten jam nut on adjustment screw.

c d

a b

a - Alignment Mark 55086 b - Casting Alignment Mark c - Link Rod a - Full Throttle Screw b - Throttle Shaft Arm c - Throttle Shaft Arm Stop d - .010 - .015 in. (0.25 mm - 0.38 mm)

90-852396 MAY 1996 ELECTRICAL - 2C-3 Timing Adjustments MAXIMUM TIMING ADJUSTMENT 1. Connect timing light to No 1 spark plug lead (TOP ! CAUTION STARBOARD BANK) Engine may be timed while cranking engine with start- 2. With engine in neutral, move throttle lever to er motor. To prevent engine from starting when being place maximum spark advance screw (b) against cranked, all spark plugs must be removed. stop. Crank engine with starter motor and adjust 1. Insert Spark Gap Tool (91-63998A1 ) into each maximum spark advance timing mark to obtain spark plug boot and attach alligator clips to good 22_ BTDC. Retighten jam nut on adjustment engine ground screw. 2. Disconnect remote fuel line from engine. 3. Connect remote control electrical harness to engine wiring harness. 4. Remove throttle cable barrel from barrel retainer. IMPORTANT: If trigger link rod was disassembled b verify that 11/16 in. (17.5mm) length is retained. a

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b - Spark Advance Screw

28246 a-11/16 in. (17.5 mm)

2C-4 - ELECTRICAL 90-852396 MAY 1996 PRIMARY PICKUP TIMING ADJUSTMENT IDLE SPEED ADJUSTMENT 1.With engine in neutral, hold throttle arm so that 1.With engine in water, connect fuel line to engine. idle stop screw (a) is against idle stop. Crank en- Start engine and allow to warm up. gine with starter motor and adjust throttle primary 2.Place engine in forward and monitor engine pickup screw (b) to align specified throttle prima- RPM. If RPM is above or below recommended ry pickup mark on timing decal with timing point- RPM (see specifications), readjust primary pick- er. Retighten jam nut on adjustment screw. up (b) screw to attain recommended engine NOTE: Primary pickup timing also determines en- speed. Retighten jam nut. Re-install throttle gine RPM, refer to “Idle Speed Adjustment” following. cable. IMPORTANT: Below 3,000 RPM the TKS ECM ad- vances idle timing 5_ until the engine reaches 104_F (40_C). Above 3,000 RPM, the TKS ECM does not affect ignition timing regardless of engine temperature. b 3.With end of throttle cable connected to throttle lever, hold throttle lever against idle stop. Adjust throttle cable barrel to slip into barrel retainer on cable anchor bracket with a very light preload of a throttle lever against idle stop. Lock barrel in place. 4.Check preload on throttle cable by placing a thin piece of paper between idle stop screw and idle stop. Preload is correct when paper can be removed without tearing but has some drag on it. 55087 Readjust cable barrel, if necessary. a-Idle Stop Screw b-Primary Pick-Up Screw IMPORTANT: Excessive preload on throttle cable will cause difficulty when shifting from forward NOTE: All timing adjustments made to engine under cranking speed conditions should be verified with en- to neutral. (Readjust throttle cable barrel, if nec- gine running and adjustments made if necessary. essary.) This is due to advance characteristics of individual ig- NOTE: Carburetors are equipped with idle mixture nition systems. adjustment screws. See carburetor specifications for mixture screw adjustment. 2.Remove timing light from No. 1 spark plug lead. NOTE: If sufficient throttle cable barrel adjustment is 3.Remove spark gap tools (91-63998A1) from each spark plug boot. not available, check for correct installation of link rod between the throttle lever and throttle cam. Each end 4.Install all spark plugs into cylinder heads. Torque of this link rod must be threaded into its plastic barrel spark plugs to 20 Ib. ft. (27 N·m) and attach spark until it bottoms against the throttle lever or throttle plug leads to spark plugs. cam casting, then turned out only far enough to obtain correct orientation of link rod (less than one turn). All timing adjustments must be reset after this proce- dure.

90-852396 MAY 1996 ELECTRICAL - 2C-5