Well I tried searching for someone with this specific problem but no dice, so here goes:
My brake fluid will leak whenever my car sits overnight, and when I come back in the morning theres fluid covering the top and all around the master cylinder, and down the side of the engine bay. However if I go step on the brake's they will apply and hold pressure just like normal leading me to assume its not a wheel cylinder seal or the seals on the pistons inside the MC, but rather the rubber grommets/oil seals where the resevoir attaches to the body of the MC?
Does this sound accurate?
I should also note the problem only arised once it started getting cold here, and it doesnt seem to leak while im driving the car oddly enough.
Slow brake fluid leak, oil resevoir seals/grommets? did search.
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0range_240
- Posts: 229
- Joined: Fri Aug 30, 2002 9:55 pm
- Car: 89 HCR32
Yeah that can happen with crappy seals. You can try to find a rebuild kit with those seals from Nissan, I've had a bit of bad luck with those seals as well with no dice from Nissan for my z31 master cylinder.
What you can do is this. Get some RTV and a siphon. Siphon out the brake fluid till you get the reservoir dry and pop the reservoir off. You'll see the piston for the master cylinder below it, it should still be immersed in brake fluid. Clean up the top part of the seal (without removing it from the master cylinder btw) and the mating surface of the reservoir and apply a thin coating of RTV to the mating surface. Pop the reservoir back onto the master cylinder and let it fully dry. We're talkin at least 8 hours buddy. So might want to do this before you go to bed. Once the stuff's all dry, pour in the brake fluid, it helps to tap the side of the reservoir where it meets up to the master a good couple of taps to get any and all air bubbles out of there while you're topping off your brake fluid.
I reckon though, the reason for the small leak is the plastic is shrinking at a faster rate than the rubber in the master cylinder is, thus causing a leak.
What you can do is this. Get some RTV and a siphon. Siphon out the brake fluid till you get the reservoir dry and pop the reservoir off. You'll see the piston for the master cylinder below it, it should still be immersed in brake fluid. Clean up the top part of the seal (without removing it from the master cylinder btw) and the mating surface of the reservoir and apply a thin coating of RTV to the mating surface. Pop the reservoir back onto the master cylinder and let it fully dry. We're talkin at least 8 hours buddy. So might want to do this before you go to bed. Once the stuff's all dry, pour in the brake fluid, it helps to tap the side of the reservoir where it meets up to the master a good couple of taps to get any and all air bubbles out of there while you're topping off your brake fluid.
I reckon though, the reason for the small leak is the plastic is shrinking at a faster rate than the rubber in the master cylinder is, thus causing a leak.
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0range_240
- Posts: 229
- Joined: Fri Aug 30, 2002 9:55 pm
- Car: 89 HCR32