Steering Gear: Service and Repair
Manual Steering Gear Service
Fig. 5 Steering gear (typical) disassembled
1. Loosen adjusting screw lock nut and remove housing side cover by removing adjusting screw.
2. Loosen lock nut and back off worm bearing adjuster several turns, then remove housing end cover and gasket.
3. Remove lower thrust bearing, steering shaft and upper bearing from housing.
4. Remove ball return guide clamps and guides from ball nut. Turn ball nut over and remove ball nut from steering shaft worm.
INSPECTION OF COMPONENTS
1. Clean and inspect all ball and roller bearings and races, including race in housing.
2. Inspect pitman shaft bushings in gear housing and end cover. If bushings are worn excessively, replace bushings.
3. It is advisable to replace pitman shaft grease seal in housing to avoid possible leakage of lubricant. Seal must be installed with feather edge toward
inside of housing.
4. Inspect pitman shaft for wear or pits in bearing races, which would require replacement of shaft.
5. Check shaft for straightness.
6. Inspect teeth of ball nut and pitman shaft. If scored or excessively worn it is advisable to replace both parts to insure proper mating of teeth.
7. Check serrations of pitman shaft; if twisted replace shaft.
8. Check fit of pitman shaft adjusting screw and shim in slot in end of pitman shaft. With shim in place, screw head must be free to turn in slot with
zero to 0.002 inch end play. If end play is excessive, selectively fit a new shim, which are available in four different thicknesses.
Lubricate all seals, bushings, bearings and gears with multi-purpose gear lube prior to installation.
1. Position ball nut over worm shaft so that deep side of teeth will be toward side cover when installed in gear housing.
2. Install exactly 1/2 the number of balls in each circuit, rocking worm shaft slightly to aid in installing balls.
3. Place about six balls in each return guide, using grease to hold balls in place.
4. Install return guides, clamp and screw.
5. Rotate worm through its complete travel several times to be sure balls are installed correctly and rotate freely.
6. Place upper bearing on worm shaft and slide worm shaft assembly into housing.