Control Valve Pump Assembly
Disassembly1. Disassemble valve body, noting the following:
Fig. 77, Control valve bodies pump exploded view. 1987-90:
a. Valves and springs are not interchangeable, keep them in the order shown, Fig. 77.
b. Position as shown and, starting at lower right, remove each valve train and lay out as shown.
c. Roll pins are under pressure, cover bore when removing them.
d. Blind hole pins must be removed with a No. 49 drill bit .073 inch (1.85 mm). Grind taper off bit.
2. Remove auxiliary valve body cover attaching bolt, then the cover and gasket.
3. Remove solenoid assembly attaching screw, then the solenoid and O-ring.
4. Remove pressure switch and governor pressure switch, if equipped.
5. Remove auxiliary valve body from main valve body.
6. On 1986 models, remove converter clutch regulator valve, pin, bore plug and spring.
7. On 1987-90 models, remove orifice control valve, spring and pin, if equipped.
8. On all models, remove converter clutch control valve and plug.
9. Remove pump slide pivot pin and pump slide.
10. Remove pump vanes and rotor, then the pump vane ring.
Inspection
1. Clean valve bodies with suitable solvent and air dry.
2. Replace Low blow off assembly with new parts.
3. Clean all valves, bushings and springs with suitable solvent and air dry.
4. Inspect valve bodies for damaged oil passages, casting porosity, machine face damage and scored valve bores.
5. Inspect pump pocket and auxiliary valve body sleeve for damage.
6. Inspect valves and bushings for scoring or cracking and check for collapsed springs.
7. Inspect following pump parts for damage; rotor, vane, vane ring, slide seals, slide O-ring seals and pump shaft bearing.
Assembly
1. If pump rotor and/or slide is damaged, replace with parts of similar height. Measurement of original rotor must be made on undamaged surface.
2. If pump shaft bearing is being replaced, proceed as follows:
a. Using pump bearing remover/installer tool No. J-35914 and No. J-7079-2, or equivalents, drive out bearing toward pump pocket.
b. Using same tools, install new bearing from pump pocket side. On 1986 models, bearing cup must be .017-.005 inch (.45-.15 mm) below pump pocket. On 1987-90 models, bearing cup must be flush to .012 inch (.3 mm) below pump pocket.
3. Assembly of pump and auxiliary valve body is the reverse of disassembly. When assembled, attach auxiliary valve body to valve body with new gasket, then install cover with retaining bolts. Refer to "Torque Specifications Chart" for torque values.
4. Assemble valve body in reverse order of disassembly.
5. Install check balls No. 2, 3, 4 and 5.
6. Place valve body spacer plate between two spacer plate gaskets and install in case, then install check ball No. 1 on spacer plate.
7. Install oil pump drive shaft, then the two 6 mm guide pins.
Fig. 78, Control valve pump assembly bolt locations:
8. Install valve body assembly onto case cover, then install valve body pipe retainer and attaching bolts as shown in Fig. 78. Apply suitable sealant to bolt "F".
9. Connect wiring harness, then install throttle lever to cable link.
10. Install throttle lever and bracket assembly, engaging link.
11. Remove 6 mm guide pins.
12. Install remaining bolts. Refer to "Torque Specifications Chart" for torque values.
13. Install cover gasket, cover and screws. Refer to "Torque Specifications Chart" for torque values.