85. Servo Assembly Overhaul

Servo Assembly Overhaul

Removal






Notice: Do not use a magnet in order to remove the control valve body ball check valves. This may magnetize the control valve body ball check valves, causing metal particles to stick to them.

1. Remove the following steel check balls:
- 1st accumulator fluid line pressure check ball (311)
- 1st clutch fluid line pressure check ball (318)
- 2nd clutch fluid line pressure check ball (319)
2. Remove the 1st accumulator choke (326).
3. Remove the clutch pressure control valve B (308), return spring (307), bore plug (309), and retainer clip (310).





4. Remove the following:
- Reverse clutch pressure control valve (313), return spring (314), bore plug (315), and retainer clip (310).
- Servo control valve (316), return spring (317), bore plug (309), and retainer clip (310).
- Shift valve C (321), return spring (320), bore plug (309), and retainer clip (310).
- Clutch pressure control valve A (323), return spring (324), bore plug (309), and retainer clip (310).
- Kick-down valve (304), kick-down short valve (305), return spring (303), and retainer plate (302).

Inspection






Caution: When you use compressed air in order to clear fluid passages and to dry parts, always aim the air pressure away from face and eyes. Always wear adequate eye protection in order to avoid injury from dirt and debris that may adhere to parts.

1. Clean all parts thoroughly and dry them with compressed air. Blow out all passages.
2. Inspect the servo valve body for scoring and damage.
3. Inspect all valves for wear or damage. If a valve does not operate, refer to General Valve Body Service.
4. Coat all parts with automatic transmission fluid during assembly.

Installation
1. Install the reverse clutch pressure control valve (313), return spring (314), bore plug (315), and retainer clip (310).
2. Install the servo control valve (316), return spring (317), bore plug (309), and retainer clip (310).
3. Install the shift valve C (321), return spring (320), bore plug (309), and retainer clip (310).
4. Install the clutch pressure control valve A, return spring (324), control valve A (323), bore plug (309), and retainer clip (310).
5. Install the kick-down short valve (305), kick-down valve (304), return spring (303), and retainer plate (302).
6. Install the clutch pressure control valve B, return spring (307), control valve B (308), bore plug (309), and retainer clip (310).





7. Install the following steel check balls in their correct passages:
- 1st accumulator fluid line pressure check ball (311)
- 1st clutch fluid line pressure check ball (318)
- 2nd clutch fluid line pressure check bail (319)
8. Install the 1st accumulator choke (326) in the direction shown in the insert.