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| | | | Joined: Oct 2006 Posts: 29 Apprentice | | Apprentice Joined: Oct 2006 Posts: 29 | I looked around and didn't find any topics that seemed to answer my particular problem adequately so here goes...
My neighbor and I replaced the innards to my master cylinder after I started noticing my brake pedal would slowly push to the floor while I was sitting at stoplights (particularly annoying on hills). Ever since then I have had some issues with the brakes. I've had to refill the master cylinder a couple of times because suddenly the fluid level would seem to drop. And then it would rise again for a while, then drop further. It's been a month or so since I last topped it off and that problem seems to have gone away, but now I have what seems to be a brake fluid expansion issue.
When I start the truck up after letting it sit, the brakes work with what I would call the proper amount of pedal travel before kicking in. But after driving for a few minutes (maybe 5?) the fluid seems to either expand dramatically or redistribute itself and I barely have to touch the pedal before the brakes kick in. I'm not even sure if I have enough pedal travel to activate the brake lights. The other day it felt as though the brakes were on while I was driving. Granted it's been unusually hot here in LA and that could be a factor, but I lived in Phoenix before this and never had this kind of problem.
I would drain a little of the fluid out, but as I said, when the engine is cold the brakes are perfect and I am worried that they will be too soft once I remove fluid. I'm not having problems braking... the truck stops fine. But I find the fluctuation rather unsettling and I'd like to even it out. I've had the truck since '97 and this is a first for me.
Has anyone else encountered this kind of problem? Known causes? Remedies?
Thanks folks!
My mechanic calls it an oil leak... I call it my truck's 'self-lubricating chassis' feature.
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | This is a common problem. You need to adjust the push rod that goes into the master cyl. It should have a small amount of free play when you push on the pedal. If not it doesnt let the MC piston come back far enough to open the compensating port. You loosen the lock nut & turn the rod to get the correct length & then tighten the locknut.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 |
How old are the flexible hoses (3 of them) in your brake system?
Tim
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