Ive been sittin in front of this computer all day
Booster or master cyl
Thread Starter
Racer
Joined: Feb 2005
Posts: 362
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From: Morristown Tn
Booster or master cyl
I have an 85 z85. Brakes have been great ....Until now... Pedal has alwys been firm. A couple of days ago I noticed the pedal getting softer,but it would pump up and hold. It still stops the car ,but if I maintain brake pressure now it will go to the floor in several second gradually. I can let off and get them back ,but they will leak down again. Is it the booster or master cyl?? It is getting worse.HELP!!!
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From: So. Cal.
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I have an 85 z85. Brakes have been great ....Until now... Pedal has alwys been firm. A couple of days ago I noticed the pedal getting softer,but it would pump up and hold. It still stops the car ,but if I maintain brake pressure now it will go to the floor in several second gradually. I can let off and get them back ,but they will leak down again. Is it the booster or master cyl?? It is getting worse.HELP!!!
Safety Car
Joined: Jan 2008
Posts: 3,939
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From: Vero Beach Florida
Check for fulid leaks around the master cylinder reservoir cup. I had the one on my 87 crack on the bottom seal so it would leak a small amount of fluid and not hold pressure. Easy fix if that is the problem.
Last edited by floridamale; Nov 21, 2009 at 07:58 PM.
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From: So. Cal.
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From: So. Cal.
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Safety Car
Joined: Sep 2004
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From: Mission Viejo CA
The leak is internal. Fluid is getting past the piston seal and is returning to the reservoir. If you see a fluid leak at the joint between the master and the brake booster, you probably have brake fluid getting into the booster. This will destroy the booster soon!
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Supporting Vendor
Joined: Mar 2008
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From: Muskegon MI
Rebuilt units are readily available, but you will have to reuse your reservoirs. You can get a new unit, but they are considerably more expensive than they used to be.
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From: Database Error Indiana
Le Mans Master
Joined: May 2006
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From: Irvine Ca
^^Yeah, OP, if you get the chance, get the MC with the Cups already on there.
It is a sad statement when the hardest part of the job is switching those cups from the old to the new.
When I went into "Destroy to remove" mode.....then the those cups came off. I'd pay a bit extra to get cups already installed.
It is a sad statement when the hardest part of the job is switching those cups from the old to the new.
When I went into "Destroy to remove" mode.....then the those cups came off. I'd pay a bit extra to get cups already installed.