[C2] braking problem
05-28-2017, 09:51 AM
#1
Melting Slicks
Thread Starter
braking problem
on my 64 with drum brakes&booster (and conversion to dual master cylinder) I have more than ample breaking power. However, for the purpose of testing out I took off the vacuum from the booster (and plugged the manifold vacuum line) just to find out that only very marginal breaking power was left! Even pushing hard on the pedal does not do it. That's kind of frightening, would not ever dare to drive it on the open road at anything above 5mph...
Any clues?
Any clues?
05-28-2017, 10:45 AM
#2
Team Owner
Member Since: Mar 2003
Location: Greenville, Indiana
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That's normal. Just push harder to stop next time you lose your booster.
Last edited by MikeM; 05-28-2017 at 12:18 PM.
05-28-2017, 11:14 AM
#3
Team Owner
You should get a small number of boosted pedal pumps before the reserve is exhausted and then yes you have to muscle the car to a stop.
Last edited by Frankie the Fink; 05-28-2017 at 11:16 AM.
05-28-2017, 11:15 AM
#4
Le Mans Master
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St. Jude Donor '05, '09, '15
Pretty typical of power assisted brakes. Try bleeding the assist off on whatever modern car you drive then brake but don't do it close to another car or heavy object! You won't be happy.
Tom
05-28-2017, 12:18 PM
#5
Team Owner
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If your dual master cylinder isn't a 7/8" bore and is larger than that, you have just increased the effort by quite a bit over what should be expected.
Try stopping a loaded diesel pickup truck pulling a loaded trailer (that uses a vacuum pump) and have the belt break that drives the pump.
Try stopping a loaded diesel pickup truck pulling a loaded trailer (that uses a vacuum pump) and have the belt break that drives the pump.