hydroboost brake leak

[garrett]

I have an 84 TR with stock brakes. About a week ago, I decided to paint my master cylinder cover with yellow caliper paint. I re-installed the master cylinder cover and everything was graet for a weeks worth of driving. Yesterday I was coming home from work and I lost most of my brakes. I managed to get home safely. When I checked out the problem, I noticed that the driver's side header and spark plug wires were wet and oily. I thought I had a failure in the power steering line that goes to the hydroboost system. This was not the case. When I took the master cylinder res cover off, it was full on the front part of the resevoir, and basically empty on the back half. I am assuming that when the system was running and pressurized, the brake fluid was forced out of the master cylinder res and it leaked down the sides of the resevoir. Is this possible? Do I now have to bleed the whole system or does the rear part of the resevoir only affect the rear brakes? Or does it only affect only the fronts?

 

[zeus87gn]

That M/C should be your typical setup, only bolted to the hydrobooster.
Trace your lines to be sure, but the rear of the m/c should service the front wheels. The front part for the rear wheels.

Theretically, the bowl should not pressurize...but the chance does exist due to the design and the speed at which the pedal is pushed/released. The cover seal must be in good shape to handle this. In addition, the cover retainer must be in good shape as well. Most likely, the seal needs replacement. They don't last forever. Try to find a good replacement, not one of those from the "HELP" section either. They aren't worth much. I don't know if a GM replacement is feasible.

You should only have to bleed the rears, but you may want to bleed them all just to be sure. Old brakes should be treated fairly all the way around.

 

[garrett]

driver's side rear blow out

I discovered that I blew out the wheel brake cylinder on the rear driver's side. I have spent all day wrestling with old rusty, frozen brakes. Fun,Fun,Fun. Now I have to bleed the rears at least. Thanks for the help.

 

[zeus87gn]

Oh the joy. Been there a number of times.

That being the case, you most certainly ought to trace your lines and be sure which side of the m/c services what. You may have a problem in your front wheels as well.

If you would please, let me know what you find when you trace your lines. It would be good information for the knowledge. Don't know much about the hydroboost, but would love to know.

 

[Martin U]

hydroboost rebuild

Does anyone have a link to a good diagram of this system? I developed a leak in mine some where up near the fire wall, it was drinking a bunch of power steering fluid. I have never had a problem before with this system and it will be the first thing I will have to rebuild in the spring.
Thanks
Mart