Clutch Master Cylinder and Reservoir

Removal

1.  CAUTION: For vehicles equipped with external clutch slave cylinders, prior to any vehicle service that requires removal of the clutch slave cylinder (i.e., transmission removal), the master cylinder push rod must be disconnected from the clutch pedal (7519). If not disconnected, permanent damage to the clutch slave cylinder will occur if the clutch pedal is depressed while the clutch slave cylinder is disconnected.

   NOTE: When replacing a dry clutch master cylinder (7A543), remove tubing from vehicle and connect to clutch master cylinder. Perform Bench Bleed Procedure in this section.

   From cab interior, carefully pry push rod and retainer bushing from cross-shaft lever pin.

2. Disconnect connector plug of the clutch pedal position switch (CPP) (11A152).

3. Remove the two nuts and support bracket retaining the clutch master cylinder reservoir and clutch master cylinder to the firewall.

4. Disconnect hydraulic tube from clutch master cylinder.

5. Remove clutch master cylinder reservoir and clutch master cylinder from firewall.

6. When the clutch master cylinder studs are free of dash panel, rotate clutch master cylinder 105 degrees counterclockwise to permit clutch pedal position switch to exit dash panel. Remove unit from vehicle.

7. Prior to installation, replace clutch and brake pedal pivot shaft lever as described in the Removal and Installation procedures in this section. Tighten nuts to 10-14 Nm (89-124 lb-in).

Installation

1. Follow removal procedures in reverse order.

2. Bleed system. Refer to the appropriate clutch hydraulic system bleeding procedure in the Adjustments portion of this section.

3. As the clutch disc (7550) wears, the fluid level in the clutch master cylinder reservoir will rise. The proper fluid level is indicated by a step on the clutch master cylinder reservoir. Do not overfill. The fill line step in the clutch master cylinder reservoir is the normal level for a new system. The upper portion of the clutch master cylinder reservoir must accept fluid that is displaced from the clutch slave cylinder as the clutch wears.

   
   
   
   
   
   

   Item	Part Number	Description
   1	2450	Brake Pedal and Bracket Assembly
   2	7A543	Clutch Master Cylinder
   3	N620481-S2	Nut
   4	7A554	Clutch Pivot Shaft Lever
   5	—	Nut (Part of 2450)
   A	—	Tighten to 10-14 Nm (89-124 Lb-In)
   B	—	Tighten to 68-92 Nm (50-68 Lb-Ft)