Wagoneer L6-242 4.0L VIN L FI (1989)
Brake Master Cylinder: Service and Repair
Master Cylinder Overhaul
Disassembly
DISASSEMBLY
1. Drain the master cylinder fluid reservoirs and place it in a vise.
2. Press the primary piston (1) inward and remove the snap ring (2).
3. Discard the primary piston.
4. Apply air pressure at the secondary outlet port (3) to remove the secondary piston assembly.
5. Remove and discard the secondary piston seals (4).
6. Replace the outlet port tube seats if necessary according to the following procedure:
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Enlarge the hole in the seats (5) using a 5.1 mm (13/64-in) drill bit.
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Place a flat washer on each outlet port and thread a 1/4-2Ox3/4 screw into the seat.
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Tighten the screw until the seat is loose and remove the seat.
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Install the seats using spare tube fitting nuts to press the seats into place.
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Remove chips or burrs and clean, rinse, and dry the master cylinder components with brake cleaning fluid and compressed air
Assembly
