No brakes after 3 week setup
 

During the poor weather we had my Pcar sat in the garage. It was left in neutral, emergency brake OFF and 2x4's in front of wheels. NO work was done to the brakes nor were the tires ever off the car, the only work I did to it was replace the steering wheel w/ a Sparco.

Sat. the weather was good so I let the car roll out the garage (did not need to start the car to do this) so I could check the tire pressure and vac. the car. When I tried to apply the brakes they went all the way to the floor. I pumped them several times 'til I finally pulled the emergency lever to stop the car from rolling. I sat for a sec and then hit the brakes a couple times again and after the 3rd or 4th try I had a full/normal pedal. I was NOT hitting the clutch and the brakes when they did come up went from no pedal at all to full "normal" pedal (they did not slowly pump up). Again, the first thing I thought was I had been hitting the clutch but I had not.

In mid-Nov I did replace the rubber brake hoses w/ stainless and bled the system fully and had no problems w/ the brakes until now. The first thing I checked was fluid level (full) and then for any dampness or sign of leaking at the stainless line fittings (none). I did wind up taking the car for a 1 hr. drive and the brakes functioned normally the whole drive.

What could have caused this? If the vacuum booster had lost vac the pedal should just be harder to push, not go all the way to the floor. Besides, I hadn't yet started the car when they came back up. I'm confused, if it wasn't a critical system like the brakes I would ignor it and see if it did it again.

Any ideas?
Bill W.

.....the only work I did to it was replace the steering wheel w/ a Sparco.

Obviously, that caused all your troubles, Bill.
(Sorry)

Many years ago I had a Mini Cooper S with a similar problem. Occassionally and without warning the brake pedal would disappear to the floor, very scary! Again no loss of fluid or other symptoms, I had the car checked out by the dealer but they found nothing wrong, and I never did sort it out but I always suspected a dodgy seal in the master cylinder

How did you bleed your brakes when you installed the stainless steel lines? If you pumped the master cylinder to bleed air from the lines you may have run the MC seals beyond their normal operating range and into a rusty section of MC bore. This can result in dirty, damaged and leaking MC seals. A new MC may be in order. Jim

I'll put my backing behind the master cylinder. I would be sitting at a light and the pedal would fade in slightly. No fluid loss, no leakage....MC.

This was only a week after buying the car....

it has to be the master cylinder. if you cut both rear brake hoses, for instance, you would still have some pedal, and front brake function, because your brakes are two seperate systems. being that you lost all braking ability, the problem has to be something that effects all the brakes. the master cylinder.

makes sense
 

OK. Yes, that's what my gut was telling me. When I bled the brakes I installed Speed Bleeders and pumped out the system and it would make sense that some crap would have been in the MC as the car only had 47K and hadn't been driven (or fully serviced) in a while. I drove it another 130 mi. today and the brakes seemed to function fine.

I see that replacement ATE MC's run apx. $120, is that the way to go or is a rebuilt kit available or is that route more trouble than it's worth?

Thanks again

OK, just did a little more research and found the rebuild kits are apx. $70 and the new MC's are apx $110 so, for me, that's a no brainer, I'll replace the MC.

For what it's worth; I was told once that there is always air in the system to some degree; it only becomes a problem when it all gets to one place. Perhaps that is what happened; it all filtered up to the highest point over the longer "stagnant" period.

Just my .02.

I see that replacement ATE MC's run apx. $120,

unless your mc has been previously replaced it is at leat 14 yrs old...

dont rebuild.....install a new one

My advice? You can cut corners on everything but brakes (and wheel nuts). Get a new master cylinder, and rebleed the system. It's not worth risking your life for. Even if it does come back, this was a warning that your system is in trouble. John was right - the brake system is a fail-safe (supposedly) system that will still hold pressure even if one of the lines are cut. Since you lost all pressure - it has to be the master cylinder...

-Wayne