427_Roadster

Last time I had the Vette out the brake pedal was feeling soft and travelling closer to the floor. When I got home, I checked the resevoirs in the master cylinder and the back one was empty. Front was still full.
From the looks of it and I could be wrong here it looks like it may be leaking from the fitting that goes into MC.
Can I wrap some teflon tape around this fitting an see what happens or do I have to bleed the MC because air may have gotten in?
I would like to replace the MC entirely because it looks like hell and they're cheap enough, but I'm not sure I really understand the whole bleeding concept. It seems like it gives better wrenchers than me alot of problems.
What's my next step? BTW- They are not power brakes.
:cheers:
-Tom


[Modified by 427_Roadster, 5:57 PM 12/7/2001]


[Modified by 427_Roadster, 5:57 PM 12/7/2001]

MikeC

Looks like you have a a leak in your back brakes.

I was always told that brake fluid and teflon tape do not mix.

You have to bleed the brakes no matter what, jack the car up and take the wheels off and check the system for leaks.

FeedVaal

Teflon tape and brake fluid is a :nono:
If you're leaking at the fitting, replace the line or M/C.

Cooter Tech

Teflon tape will not help, your brake fluid is leaking out, at the fitting as you suggest, or a brake line, or a wheel cylinder. Brake pads could even be badly worn. As pretty as that car is and if you are not comfortable with working on the brake system, let a good mechanic work on it, do not take any chances with that car. Roger L. Gibbons

Rockn-Roll

If a m/c reservoir is empty then you need to completely bleed everything...I'm surprised your brake light didn't come on so be sure it lights up when you start the car, and when you engage the emergency brake, then check the connection at the distribution/proportioning valve.

First thing I would do in this situation is jack up the rear (both tires off the ground) and remove the rear wheels and inspect the calipers for leakage, check for pad thickness, and rotor for signs of gouging if the pads wore all the way down. If it needs pads or there's signs of leakage then I would remove the calipers and replace the calipers with new ones if there was leakage, and install new pads if it needs them. I would then fill the m/c up with fluid and bleed the rear brakes until I get clear fluid with no bubbles, then bleed the front brakes until I get clear fluid with no bubbles, then bleed the rear again, then finish with a second front brake bleeding. I would then look around for any more leaks and test drive it. If everything is working OK, then I let it be and recheck after about 10 miles of city street driving.

Your symptoms sound almost like a m/c problem, but m/c's are designed so that if there's a failure with the m/c then all the fluid would get pumped into the rear reservoir and not the front...which would also cause it to leak out the top of the m/c, and appear to be a leak in the fitting. Also, brake fluid will eat teflon tape so don't use it there...buy a new line, or get a hose flaring tool and new fitting to repair a leaky connection that doesn't seal when you take it out, clean it, and tighten it back on.

427_Roadster

OK Here's an update...
Took the rear tires off and inspected the calipers and lines. Everything's dry and looks good. The lines are actually pretty new looking. The pads look brand new also.
So I guess back to the MC - looked from under the dash at the linkage from the brake pedal going through the boot into the firewall, it looks like it is wet with brake fluid. Don't know if this means anything it could be just what ran down the back of the MC. Took of the back brake line fitting on the MC and it seemed pretty tight, but it still looks like that was where the leakage occured.
With that in mind, do you think I should just replace the MC?
Thanks for the help :cheers:
-Tom


[Modified by 427_Roadster, 10:07 PM 12/7/2001]

Brian Madderom

I would definately change the master cylinder! The first indication that it is going bad is the fluid on the boot inside the firewall where the shaft goes from the brake pedal. Also there is no fluid leaking on the rear calipers. :flag

Chuck Gongloff

Another thought..if you're into "originality", and you have the original master cylinder in the car, it can be re sleeved and rebuilt. Many Corvette companies offer this service. It can be resleeved in either stainless steel or brass. Chuck