loss of brake fluid when cold, why?
 

ok, yet another little problem with my car(its an 87 t2). its been getting colder where i live and i got in my car the other morning only to find that i had no brakes. all my fluid had leaked out of the resevior over night. it has done this before when i went to tahoe in the winter, but it hasn't happened in sacramento before. i can see the fluid has eaten away the paint under the resevior, so i know its just dripping straight down, but from where. are there little o rings in the resevior that shrink when its cold, letting out all the fluid. anyone have this problem before. how do i fix it. any help appreciated. thanks

CR

I've had mine leak alittle in the winter but never lost all my fluid in one night.I think(at least on mine)that it is the seals where the resivior goes into the master cylinder.I don't know if you can get them seperate or if you have to buy the whole rebuild kit.My clutch master cylinder is starting to do the same thing.

You may have more problems than just those seals I mentioned 'cause I'm sure it gets way colder here in TN than in CA and I've yet to lose that much fluid in one night.Maybe someone else will have more insight as to the problem.

thanks DAK, i was thinking it was these seals. are there other seals in the master cylinder or brake booster that i should look at? where would the fluid come out of? ill take a closer look at this stuff tomorrow and see what i find.

CR

Sorry I can't help with your question. Just wanted to say hey, it was cool talking to you at school the other day.

good to meet you to chance. ive seen your car for so long now and never knew who it was. talk to you later.

CR

Do you have fluid on the brake master cylinder? If so you are going to have to change the seals between the master cylinder and the brake fluid reservoir.

I can almost guarantee the rubber seals between the fluid reserviour and the body of the master cylinder have failed. The rubber gets hard with age and seems to be ok in warm weather but leaks in the cold - try rocking the reserviour from side to side and you will probably see fluid squishing around the two seals - same problem with the clutch reserviour - they just pop off although some cars have a holding screw as well. Be warned though - they are a bitch to replace as they are a very tight fit and awkward to try and force in place.
Ian

Ya know, i was wondering the same thing... My cars been out of commission for a few weeks due to a bad clutch, and when i went to look it over the other day the brake fluid resevoir was empty. Lol, you can imagine my reaction seeings how i just bought all new clutch hydraulics :rolleyes: i was thinking now it was time for new brake stuff as well. I'll have to look into this, mazda or mazdatrix probably sells the little o rings, maybe new ones would be the easiest way to go.

~Jesse