SKINNED KNUCKLES LARES ARTICLE CORPORATION Orest LazarowichPresents Looking Backward but Moving Forward A Continuing Series focused on the Repair and Restoration of your old Car and Truck. Manual Steering Gear and Linkage There are four common manual steering gears in use. The worm and sector, worm and The steering gear mechanism allows the roller, recirculating ball steering and the rack and driver to turn the front wheels of the vehicle. pinion. In the worm and sector style the worm is This includes the steering wheel, steering gear connected at the end of the steering shaft. The box, pitman arm, drag link, tie rods, steering sector is mounted on a sector shaft. The teeth of arms, and steering knuckles which support the the worm mesh with the teeth of the sector. The wheels. Turning the steering wheel left or right friction value is very high in this design because turns the steering shaft to which a worm gear is most of the load is concentrated on the gears at attached within the gear box. The steering worm their mesh point. The worm and roller is similar gear moves the sector gear, and this motion is to the worm and sector type. A toothed roller is transmitted to the pitman arm which moves fore mounted on a roller shaft, and a worm gear is and aft. A drag link connected to the pitman arm mounted on the steering shaft. Gear teeth of the transmits this movement to the tie rods which are worm gear mesh with the roller, and motion is connected to the steering arms. The steering transmitted. The roller is mounted on a ball bear- arms turn the steering knuckles and the wheels ing. This bearing provided low friction as it took which are pivoted left or right on the front end the load, and the roller distributed the wear more suspension. evenly. The recirculating ball steering offers ex- tremely low friction and power loss. A ball nut Steering Wheel on bearings is meshed with the worm gear and Tie Rod screws up and down relative to the movement of the worm. The rack and pinion steering consists of a pinion attached to the steering Magazine. shaft which meshes with a flat rack. The pin- Center Link ion travels left or right on the rack to move the road wheels. Idler Arm Steering linkage arrangements vary de- Knuckles Skinned pending upon need and basic design. There are Tie Rod Gear Box two basic types of steering control systems; those that have a pitman arm and a steering box, and those that use rack and pinion steer- ing. The most common type of steering using Pitman Arm a pitman arm is the parallelogram type. It uses PAGE 12 - SKINNED KNUCKLES Article content provided by Lares Corporation Steering Components • CALL 1.800.555.0767 • VISIT www.LaresCorp.com SKINNED KNUCKLES LARES ARTICLE CORPORATION Worm Gear Worm Pinion Gear Roller Rack Roller Bearing Recirculating Ball Steering Rack and Pinion Sector Worm and Sector Worm and Roller Four Common Manual Steering Gears two tie rods and a center link between the tie rods line imbalance or unequal weight distribution be- There is an idler arm on the passenger side and tween the wheels. Inspect the shock absorbers or the pitman arm on the driver’s side that attach to struts for loose mounting bushings and bolts. Ex- the center link. When the steering wheel is turned amine for leaks. Inspect the wheel bearings for the center link transfers the movement to the lateral movement. Inspect the steering linkages steering arms and outer tie rods. All of the joints and tie rod ends for wear (looseness). Inspect for which mount these components use small ball loose steering gear mounting bolts, worn mount- joints to provide the freedom of movement. The ing brackets and bushings. Replace worn parts, two sides of the linkage run parallel to each other and/or adjust front wheel bearings. and are equal in distance thereby forming a par- allelogram steering linkage. In the rack and pin- Manual Steering Gear ion system the center rod is replaced with a steering rack which is a long, toothed bar with tie The gearbox is attached to the frame, and rods attached to each end. On the end of the steer- it can be directly connected to the steering shaft ing shaft there is a pinion gear that meshes with and wheel or by a U-joint/rag joint. Check for the rack. When the steering wheel is turned, the excessive free play (more than 1½ - 2") at the pinion gear turns, and it moves the rack from left steering wheel. to right. Changing the size of the pinion gear Check the steer- changes the steering ratio. ing shaft U- joint/rag joint for Road Test wear, if the steer- Flex ing gear is of this Housing During the road test, listen for any unusual style. If they are noises related to the suspension and steering. worn, replace Gear Box Check for steering problems such as: steering them. Check that wander or drift, high steering effort and binding, the pitman arm is Frame Magazine. excessive steering wheel free play, steering wheel tight to the sector return and front wheel shimmy. Back at the shop shaft. The steering raise the front of the vehicle on safety stands. In- wheel should start Pitman Arm spect for worn suspension parts and/or worn tires. to move the pit- Hard steering can be caused by damaged steering man arm within Knuckles Skinned linkage, worn steering linkage, damaged spindles the approved and bent steering arms causing incorrect turning range. If it doesn't, there is an adjustment at the angles. Front tire shimmy can be caused by tire gearbox to tighten up the free play. There are two imbalance and/or tire runout. Vehicle instability adjustments: the worm bearing preload and the can be caused by driveline misalignment, drive- sector shaft mesh. Check lubricant level, and if it is low, check for a gasket leak, sector shaft seal JUNE 2016 - PAGE 13 Article content provided by Lares Corporation Steering Components • CALL 1.800.555.0767 • VISIT www.LaresCorp.com SKINNED KNUCKLES LARES ARTICLE CORPORATION leak or a cracked gearbox. To replace the seal the friction. Two Gemmer designs were popular. pitman arm has to be removed. If the gearbox is The 1937-52 Ford models used a two-tooth cracked, check with the local parts recycler. roller, and the 1953-60 models use a three-tooth roller which provides longer service life. There Replacing Rag Joint are several wear points, (the worm teeth and roller teeth and the upper and lower worm bush- The rag joint is basically a vibration ings), but they can be adjusted The sector shaft dampener. It keeps the chassis vibration from bushings and oil seal are replaceable. transferring through the steering column to the steering wheel. It can also correct a slight mis- Adjusting Steering Shaft Bearing Preload alignment of the steering shaft and gearbox. Kits are available to Sit in the driver's position, and check for replace the rag steering shaft endplay by pulling/pushing on the joint with a uni- steering wheel. If there is endplay, it must be ad- versal joint. justed out to set the bearing preload. Power wash Cover the left the gearbox and pitman shaft area. Raise the fender with a front of the vehicle on safety stands. Remove the fender cover to left front tire and wheel. Disconnect the steering prevent a belt linkage (drag link) from the pitman arm. If the buckle from mar- ball on the pitman arm is worn oval, replace the ring the paint fin- pitman arm. Move the pitman arm up/down and ish. To replace a sideways. If there is movement here and oil is rag joint remove leaking past the oil seal, the bushings need to be the bolts that hold replaced. If the sector shaft is worn in this area, the coupler to the you are taking on an expen$ive repair. If pitman steering box and arm movement is not excessive, you can try a steering shaft. Loosen the steering column new seal. The pitman arm has to be removed to brackets so you can pull it back to remove the install a new seal. Check the torque on the pit- steering shaft from the coupler. Remove the cou- man arm nut. It can range to over 200 foot pler from the gearbox. Take the coupler to the pounds on some vehicles. Tight it must be. auto parts store, and purchase a rebuild kit that includes new bolts and washers, if you Slide under the vehicle on a creeper, and want/need the experience of rebuilding, or go for locate the four bolts that hold the end cover in a new coupler. Install the new or rebuilt rag joint place. Find a container to catch any oil. Remove in the vehicle. Excessive steering wheel free play the bolts, and carefully separate the shims using is now corrected, if this was the problem. If not, a box cutter. You will find the metal shims are the steering gear may need adjustment. easier to separate then the paper ones. Remove one shim at a time by slitting the top edge of the Adjusting Worm and Roller shim, if the horn wire is in place. Retighten the bolts, and check for end play by turning the steer- Magazine. The worm and roller type of gearbox was ing wheel full right and left. Repeat this proce- introduced in 1926 and is still being used today.