Forward and Overrun Clutches

COMPONENTS

DISASSEMBLY




1. Check operation of forward clutch and overrun clutch.
a. Install bearing retainer on forward clutch drum.
b. Apply compressed air to oil hole of forward clutch drum.
c. Check to see that retaining plate moves to snap ring.
d. If retaining plate does not move to snap ring, O-ring or oil seal may be damaged or fluid may be leaking at piston check ball.




2. Remove snap ring for forward clutch.
3. Remove drive plates, driven plates, retaining plate and dish plate for forward clutch.




4. Remove snap ring for overrun clutch.
5. Remove drive plates, driven plates, retaining plate and dish plate for overrun clutch.




6. Set Tool on spring retainer and remove snap ring from forward clutch drum while compressing return springs.
- Set Tool directly over return springs.
- Do not expand snap ring excessively.

7. Remove spring retainer and return springs.
- Do not remove return springs from spring retainer.




8. Remove forward clutch piston with overrun clutch piston from forward clutch drum by turning it.




9. Remove overrun clutch piston from forward clutch piston by turning it.




10. Remove D-rings and oil seals from forward clutch piston and overrun clutch piston.

INSPECTION
Snap rings, spring retainer and return springs
- Check for deformation, fatigue or damage.
- Replace if necessary.
- When replacing spring retainer and return springs, replace them as a set.




Forward clutch and overrun clutch drive plates
- Check facing for burns, cracks or damage.
- Measure thickness of facing.

Thickness of drive plate:
Forward clutch
Standard value: 1.6 mm (0.063 in)
Wear limit: 1.4 mm (0.055 in)

Overrun clutch
Standard value: 1.6 mm (0.063 in)
Wear limit: 1.4 mm (0.055 in)

- If not within wear limit, replace.




Forward clutch and overrun clutch dish plates
- Check for deformation or damage.
- Measure thickness of dish plate.

Thickness of dish plate:
Forward clutch 2.7 mm (0.106 in)
Overrun clutch 2.7 mm (0.106 in)

- If deformed or fatigued, replace.




Forward clutch drum
- Make sure that check balls are not fixed.
- Apply compressed air to check ball oil hole from outside of forward clutch drum to make sure that air leaks past ball.
- Apply compressed air to oil hole from inside of forward clutch drum to make sure that there is no air leakage.




Overrun clutch piston
- Make sure that check balls are not fixed.
- Apply compressed air to check ball oil hole opposite the return spring to make sure that there is no air leakage.
- Apply compressed air to oil hole on return spring side to make sure that air leaks past ball.

ASSEMBLY




1. Install D-rings and oil seals on forward clutch piston and overrun clutch piston.
- Take care with direction of oil seal.
- Apply A.T.F. to both parts.




2. Install overrun clutch piston assembly on forward clutch piston by turning it slowly.
- Apply A.T.F. to inner surface of forward clutch piston.




3. Install forward clutch piston assembly on forward clutch drum by turning it slowly.
- Apply A.T.F. to inner surface of drum.




4. Install return spring on overrun clutch piston.
5. Install spring retainer on return springs.




- Align the mark on spring retainer with check ball in overrun clutch piston.




6. Set Tool on spring retainer and install snap ring while compressing return springs.
- Set Tool directly over return springs.




- Do not align snap ring gap with spring retainer stopper.

7. Install drive plates, driven plates, retaining plate and dish plate for overrun clutch.




- Take care with order of plates.

8. Install snap ring for overrun clutch.




9. Measure clearance between overrun clutch retaining plate and snap ring.
If not within allowable limit, select proper retaining plate.

Specified clearance: Standard 0.7 - 1.1 mm (0.028 - 0.043 in)
Allowable limit 1.7 mm (0.067 in)
Overrun clutch retaining plate: Refer to S.D.S.




10. Install drive plates, driven plates, retaining plate and dish plate for forward clutch.
- Take care with order of plates.

11. Install snap ring for forward clutch.




12. Measure clearance between forward clutch retaining plate and snap ring.

if not within allowable limit, select proper retaining plate.

Specified clearance: Standard 0.45 - 0.85 mm (0.0177 - 0.0335 in)
Allowable limit 1.85 mm (0.0728 in)
Forward clutch retaining plate: Refer to S.D.S.




13. Check operation of forward clutch.
Refer to "DISASSEMBLY" of Forward Clutch and Overrun Clutch.

14. Check operation of overrun clutch.
Refer to "DISASSEMBLY" of Forward Clutch and Overrun Clutch.