Got new Brake Booster, How to test Master Cylinder?
bishopalstare
08-25-2004, 12:03 PM
I just bought a new brake booster for my 1988 Jeep Cherokee with the I6. I don't want to replace this booster and then have it get broken again b/c of a possibly bad Master Cylinder. Is there any way to test the master cylinder so I would know that it's ok to use my current Master Cylinder with my new Brake Booster? Any help. Thanks guys and what a great site you have here. Later
Kevin
Kevin
JDPascal
08-25-2004, 08:23 PM
Hi Kevin
There is a couple of ways to look at this.
first way.
Is it leaking? Is there any brake fluid around the mounting flange? What about the fluid condition? Drag you finger in the bottom of the reservoir. What does your finger bring up?
Was the pedal firm or did the pedal sink under your foot when you steped on the pedal hard.
If any of these are questionable I believe it would be best to replace it now when you have it apart.
Second way
Replace it because it probably hasn't been replaced before and for the price of a rebuilt it's good reasurance.
Myself - I'd replace it if I had a question about any of the above.
-------------------------------------
When replaceing the master cylinder and or booster make sure that the length of the push rod in the booster is the correct length.
If it is too long, the brakes will drag and lock up because the compensating port in the reservoir will be blocked by the partially applied piston.
If it is too short, you have extra pedal travel and low pedal when brakes are applied.
Make sure you bleed the new master cylinder ON THE BENCH like the instructions tell you. If you don't, there can be all kinds of problems getting rid of spongy brakes.
JD
There is a couple of ways to look at this.
first way.
Is it leaking? Is there any brake fluid around the mounting flange? What about the fluid condition? Drag you finger in the bottom of the reservoir. What does your finger bring up?
Was the pedal firm or did the pedal sink under your foot when you steped on the pedal hard.
If any of these are questionable I believe it would be best to replace it now when you have it apart.
Second way
Replace it because it probably hasn't been replaced before and for the price of a rebuilt it's good reasurance.
Myself - I'd replace it if I had a question about any of the above.
-------------------------------------
When replaceing the master cylinder and or booster make sure that the length of the push rod in the booster is the correct length.
If it is too long, the brakes will drag and lock up because the compensating port in the reservoir will be blocked by the partially applied piston.
If it is too short, you have extra pedal travel and low pedal when brakes are applied.
Make sure you bleed the new master cylinder ON THE BENCH like the instructions tell you. If you don't, there can be all kinds of problems getting rid of spongy brakes.
JD
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