Steering Gear: Disassembly
- Clean exterior of gear housing and install it in a suitable holding fixture. Drain steering gear through pressure and return connections by turning steering worm shaft lock-to-lock several times. Remove valve body attaching screws, valve body and the three "O" rings. Remove pivot lever and spring.CAUTION: Use care not to collapse slotted end of valve lever as this will destroy bearing tolerances of spherical head.
- Loosen sector shaft adjusting screw lock nut and remove sector shaft cover spanner nut with a suitable tool (C-3988). Rotate worm shaft to position sector shaft sector teeth at center of piston travel. Loosen steering power train retaining nut with a suitable tool (C-3989).
- Turn worm shaft to full left turn position to compress power train parts. Remove power train retaining nut and housing head tang washer. With power train firmly compressed, pry against piston teeth with a screwdriver using sector shaft gear teeth as a fulcrum, and remove complete power train.NOTE: It is important that cylinder head, center race, spacer assembly and housing head be maintained in close contact with each other. This eliminates possibility of reaction rings becoming disengaged from grooves in cylinder head and housing head which prevents center spacer separating from center race and becoming cocked in housing. This would make it impossible to remove power train without damaging spacer or housing.
- Place power train vertically in a soft jawed vise.NOTE: If worm shaft oil seal is to be replaced, replace seal with housing head assembled in steering gear housing.
Remove housing head from worm shaft and "O" ring from groove in housing head. Remove reaction seal from groove in face of housing head with compressed air directed into ferrule chamber. Remove reaction spring, reaction ring, worm balancing ring and spacer.
- Hold worm shaft from turning, then turn nut to release staked portions from knurled section and remove nut. Wire brush knurled sections to remove metal chips, then blow out nut and worm shaft to remove any metal particles. Remove upper thrust bearing race (thin) and upper thrust bearing. Remove center bearing race, then lower thrust bearing and bearing race (thick). Remove lower reaction ring and spring, then cylinder head assembly.
- Remove "O" rings from outer grooves in cylinder head. Remove reaction "O" ring from groove in face of cylinder head by directing air pressure into oil hole between the two "O" ring grooves. Remove snap ring, sleeve and rectangular oil seal ring from cylinder head counterbore. Test operation of worm shaft. Torque required to rotate worm shaft throughout its travel in or out of piston should not exceed 1 1/2 INCH lbs.NOTE: Worm and piston is serviced as an assembly and should not be disassembled.
- Test for excessive side play with piston held in vise (rack teeth up) and worm in its approximate center of travel. Vertical side play measured at a point 2 5/16" from the piston flange should not exceed 0.008" when end of worm is lifted with a force of one lb.