Forward and Overrun Clutches: 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.
  1. Thickness of drive plate: Forward clutch 
  2. Standard value: 1.6 mm (0.063 in) 
  3. Wear limit: 1.4 mm (0.055 in) 
  4. Overrun clutch 
  5. Standard value: 1.6 mm (0.063 in) 
  6. 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.
  1. Thickness of dish plate: Forward clutch 2.7 mm (0.106 in) 
  2. 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. Make sure air leaks past ball.
• Apply compressed air to oil hole from inside of forward clutch drum. Make sure 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. Make sure there is no air leakage.
• Apply compressed air to oil hole on return spring side. Make sure that air leaks past ball.