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Confirm Diagnosis

kyreb1862

Jedi Knight
Offline
When I press hard on the brake pedal in my 77B the idle speeds up. Am I correct in assuming that my brake booster has gone bad?

Regards John
 
Hmm, that is a good question. It could be that the booster is gone, but it could also be a leak, maybe at the valve on the booster.

I can't recall exactly how to do it, but I know there is a test to see if the booster holds vacuum (from a pump or gauge like a Mitivac).
 
check valve or booster. A vacuum pump is the best way to isolate which. It ~sounds~ like the check valve is the culprit.
 
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