Leaky master cylinder
Thread Starter
Racer
Joined: Oct 2000
Posts: 309
Likes: 0
From: new zealand
Leaky master cylinder
Noticed the paint peeling on my master cylinder. Yeo leaky fluid.
Coming from the top of the cylinder. Checked the rubber gasket and it appeared ok. Cleaned it up and put it back on after repaint and yep.. now leaking again.
New rubber gasket ??
Is this common or is my system pressurising itself.
Had the car 12 months and first problem although it has sat for 4 months while I did the interior.
Coming from the top of the cylinder. Checked the rubber gasket and it appeared ok. Cleaned it up and put it back on after repaint and yep.. now leaking again.
New rubber gasket ??
Is this common or is my system pressurising itself.
Had the car 12 months and first problem although it has sat for 4 months while I did the interior.
Burning Brakes
Joined: Aug 2004
Posts: 856
Likes: 2
From: Tyler Texas
If you are sure it is leaking from the Master Cyl reservoir itself, then (1) I would replace the cap/cover and rubber gasket first. The covers are not expensive. The cover rubber gasket may have a tear in it or may just no longer be sealing well. (2) Also be sure the brake fluid level is correct. Many people overfill the Master Cyl reservoir. The GM service chasis manual has an illustration showing the correct level.
When the Master cyl itself leaks, it is usually seen leaking on the bottom rear side where it is attached to the brake booster.
When the Master cyl itself leaks, it is usually seen leaking on the bottom rear side where it is attached to the brake booster.
Burning Brakes
Joined: Aug 2004
Posts: 856
Likes: 2
From: Tyler Texas
My neighbor just had this same problem on his camaro and I recalled this previous thread. The new rubber MC gasket was not sealing tightly on the rear of the master cylinder reservoir--fluid was leaking between the metal cover and the reservoir. ( The MC and brake booster were new) We looked closely at the gasket as installed in the metal reservoir cover and noticed it was not a perfectly tight fit on the ends.
Solution: While reinstalling the metal reservoir MC cap/cover, we pulled slightly (toward the firewall) on the rear "ear" of the rubber gasket that protrudes out. Then kept firm downward pressure on the cover while putting the two metal bail covers in place. So far, no leaks. The problem was the new rubber MC gasket not fitting 100% correctly.
Solution: While reinstalling the metal reservoir MC cap/cover, we pulled slightly (toward the firewall) on the rear "ear" of the rubber gasket that protrudes out. Then kept firm downward pressure on the cover while putting the two metal bail covers in place. So far, no leaks. The problem was the new rubber MC gasket not fitting 100% correctly.
