Index of all Tutorials

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Tools and supplies needed:

-10mm and 12mm open end wrench
-lots of brake fluid DOT3
-safety goggles
-new master cylinder
-rag
-dowel (philips screwdriver will work) to push piston in to bleed master
-container to catch dripping fluid
-equipment to bleed brakes

CAUTION: I know nothing. Refer to factory service manuals and other experts before doing this. This "tutorial" is just my experience . Research safety issues as I know nothing about safety.

The bubbling paint on the brake booster is a good indication that brake master cylinder seal is leaking. Replacing the entire master cylinder seems the best way to go.

Click on pics to get bigger sizes

This is the refurbished master cylinder I got from NAPA for $61U.S.. The three lines are temporary lines for bench bleeding the master cylinder.
The white plastic reservoir is reused.(the bleed kit came with the master but did not work well)

This is the booster area after master cylinder is removed. Dont touch anything here.

This shows how much fluid came out and what position to hold master cylinder so fluid does not drip out of proportioning valves.

always wear goggles.
1.Clean the lines etc before opening. You dont need to drain the system.
2.Loosen the brake lines with a 10mm open end wrench. these nuts are damaged easily. WD40 them and use snapping motion instead of slow turn.
Dont unfasten these until 12mm bolts are off as they are the only thing that drips fluid.(threads in master cylinder also easy to strip)
3. Remove the 2 12mm nuts holding the master to the booster. No fluid comes out of this area, ironically.
4. Disconnect the 3 loosened lines. Have a container to catch fluid and face proportioning valves up so they dont leak. see picture. The lines stop dripping but not the 3 proportioning valves on master cylinder. Plug the lines to prevent contamination getting in.
5.Remove master from car with proportioning valves facing up. Empty any remaining fluid.
6.Remove reservoir off of old master cylinder. Use a wooden wedge as seen in picture.
6.a. Lubricate the grommets and reservoir neck with brake fluid. The grommets are seals that the reservoir neck is pushed into.

7.Put recycled reservoir on new master cylinder. Concentrate your weight on one side at a time as pictured. Make sure electrical outlet facing right direction!

8. set up new master in vise on a work bench. Install bleeding kit with hoses routed back into the fluid reservoir. I didnt need vise.See picture.
Add fluid to reservoir.

9. bench bleed master till no air is seen traveling through bleeder kit hoses:
With philip head screw driver or wooden dowel slowly push the master cylinder piston in about one inch. Then, release the piston slowly. See screw driver in pic . This is where you push the piston.

10. install master back in car in reverse order. look for leaks.
11. bleed. Brake pedal free play should be 15 mm.

****BRAKE BLEEDING PROCEDURE(non-ABS)********************

1.driver rear
2.passenger rear
3.driver front
4.passenger front

Method#1- Use a container of used brake fluid. Connect one end of a clear vinyl hose to bleeder screw and submerge the other end in container of used brake fluid. Pump the brakes with screw closed. Slowly open screw and allow air to escape. Repeat. You want to minimize the amount of fluid coming out because you need to keep the master cylinder topped up or air gets in.
Method#2-Use a vacuum pump. create a vacuum in clear vinyl hose and then slowly open up bleed screw. Repeat. Pump the brakes when the screw is closed. You dont want fluid in your vacuum pump.
Method#3-two man job. see fsm.

You must insure that your brake master cylinder does not run out of brake fluid. Otherwise, you've negated everything you've done by allowing air into the lines.

Once you're finished bleeding, pump the brakes until they're stiff before turning the car on. This insures proper pedal feel.

Links

http://www.misterfixit.com/brakbld1.htm

Modified by vancouverbc at 7:50 PM 4/16/2009