TR6 TR6 Brakes are gone-- HELP!!!

[delisaj]

Had the TR6 out less than a week ago. No problems. Went to take it out today for a ride, and, the brake pedal goes to the floor. No pressure. There is plenty of break fluid in the container. Any ideas as to where to look?

As always, thanks in advance for your insight and expertise.
Bummer. It's a beautiful New England day.

 

[swift6]

Are there any puddles near any of the wheels? if not, you probably need a new or rebuilt master cylinder (if it can be rebuilt, won't know till it's apart).

 

[delisaj]

Shawn, thanks for the insight. The first time they went, after about 3 months of driving the car, I was out of break fluid. There is a small leak of black fluid that I haven't identified, but it was in the center of the car, not by the wheels. Thought it could have been a brake line, but couldn't find it. The oil level has been fine everytime.

This time, there is plenty of brake fluid, and, rear brakes (rear cylinders and shoes are new), and the front brakes were fine. Just no pressure. Sounds like the master cylinder.

 

[DougF]

If your leak of black fluid was indeed brake fluid, the color would be an indicator that the cylinder needs rebuilt.
As the plunger deteriorates, it washes off in the fluid, eventually leaving a poor seal.

 

[jerrybny]

If your resovior was empty and you filled it back up you probably have air in the lines. This is why the pedal goes to the floor even though you have fluid. Of course the first thing you need to do is find where it is leaking from.

 

[boxofparts]

Similar thing on a TR6 I am working on.. We installed a new master cylinder and it still won't build pressure. What does the pressure switch block do? Can it leak back into the master?

 

[delisaj]

I checked the servo and the master cylinder. Servco checks out fine. Found the leak in the master cylinder, so I ordered a replacement. I shuold have in before the end of the week. I'll keep you posted.

 

[Andrew Mace]

[ QUOTE ]
....What does the pressure switch block do? Can it leak back into the master?

[/ QUOTE ]If you mean the pressure differential warning actuator (PDWA), no, it can't. All it does is detect a pressure DIFFERENCE between front and rear circuits and trip the warning light accordingly. Unless it leaks itself (which is not unknown but not very common), it can and will have no other effect.