Steering Gear: Disassembly
- Clean exterior of unit and install unit in suitable holding fixture. Drain steering gear through pressure and return connections by turning steering wormshaft from one extreme of travel to the other. Remove valve body attaching screws, and remove valve body and 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 locknut, and remove sector shaft cover spanner nut with a suitable tool (C-3988). Rotate wormshaft to position sector shaft sector teeth at center of piston travel. Loosen steering power train retaining nut with a suitable tool (C-3989). Place suitable tool (C-3786) on threaded end of sector shaft and slide tool into housing until both tool and shaft are engaged with bearings.
- 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 on piston teeth with a screwdriver using gear shaft as a fulcrum and remove complete power train.NOTE: It is important, cylinder head, center race and spacer assembly and housing head be maintained in close contact with each other to eliminate possibility of reaction rings becoming disengaged from grooves in cylinder head and housing head and prevent 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. Raise housing head until worm shaft oil seal just clears top of worm shaft, position arbor tool (C-3929) on top of worm shaft and extending into oil seal. Keeping arbor in position, pull up on housing head until arbor is fully positioned in bearing, then remove head and arbor.NOTE: Worm and piston serviced as an assembly and should not be disassembled.CAUTION: If worm shaft oil seal is to be replaced, perform operation with housing head assembled in steering gear housing head.
Remove large "O" ring from groove in housing head. Remove reaction seal from groove in face of housing head with air pressure directed into ferrule chamber. Inspect all grooves for burrs. Remove reaction spring, reaction ring, worm balancing ring and spacer.
- Hold worm shaft from turning, turn nut to release staked portions from knurled section and remove nut.NOTE: Wire brush knurled sections to remove chips, then blow out nut and wormshaft to remove metal particles.
Remove upper thrust bearing race (thin) and upper thrust bearing. Remove center bearing race. Remove lower thrust bearing and bearing race (thick). Remove lower reaction ring and spring. Remove 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 sea! ring from cylinder head counterbore. Test operation of worm shaft. Torque required to rotate worm shaft throughout its travel in or out of piston must not exceed 2 INCH lbs. with a 15 pound side load. Worm should run in and out of piston under its own weight.NOTE: Worm and piston 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.008" when end of worm is lifted with a force of 1 pound.