Brake Proportioning/Combination Valve: Service and Repair
Important: Do not wash proportioning valve in any cleaning solution. The internal components are prelubricated with a special grease.
REMOVE OR DISCONNECT
1. ABS hydraulic modulator/master cylinder.
2. Master cylinder reservoir.
3. Proportioning valve caps.
4. 0-rings.
5. Springs.
6. Proportioning valve pistons.
- Use needlenose pliers with care not to scratch or otherwise damage piston stems.
7. Proportioning valve seals from pistons.
Inspect
- Proportioning valve pistons for corrosion or deformation and replace if found.
Clean
- All parts in clean, denatured alcohol. Dry with nonlubricated, compressed air.
INSTALL OR CONNECT
NOTICE: Always use the correct fastener in the proper location. When you replace a fastener, use ONLY the exact part number for that application. the manufacturer will call out those fasteners that require a replacement after removal. The manufacturer will also call out the fasteners that require thread lockers or thread sealant. UNLESS OTHERWISE SPECIFIED, do not use supplemental coatings (paints, greases, or other corrosion inhibitors) on threaded fasteners or fastener joint interfaces. Generally, such coatings adversely affect the fastener torque and the joint clamping force, and may damage the fastener. When you install fasteners, use the correct tightening sequence and specifications. Following these instructions can help you avoid damage to parts and systems.
1. Lubricate new 0-rings and proportioning valve seals with silicone grease supplied in repair kit. Also lubricate stem of proportioning valve pistons.
2. New seals on proportioning valve pistons with seal lips facing upward toward cap.
3. Proportioning valve pistons and seals in master cylinder body.
4. Springs in master cylinder body.
5. New 0-rings in grooves in proportioning valve caps.
6. Proportioning valve caps in master cylinder body.
- Tighten proportioning valve caps to 27 Nm (20 ft. lbs.).
7. Master cylinder reservoir.
8. ABS hydraulic modulator/master cylinder.