Moparts

Ran Brake Master Cylinder Dry...

Posted By: GetAwayDriver

Ran Brake Master Cylinder Dry... - 05/01/11 03:33 PM

A friend of mine with a 2002 Ford Escape (abs) ran their master cylinder dry. I added fluid (didn't take too much) and as expected, the pedal DID NOT return to normal. Evidently, an air-pocket now in the system.

Do any of you full-time mechanics know a trick that would save me bleeding the whole system one wheel at a time? I can't think of anything, but I'd love to be proven wrong. Does ABS complicate this any?
Posted By: buildanother

Re: Ran Brake Master Cylinder Dry... - 05/01/11 04:27 PM

Did you look at brake pads and check for leak first?
Posted By: RapidRobert

Re: Ran Brake Master Cylinder Dry... - 05/01/11 04:29 PM

Dont know ABS so almost hesitant to throw anything out there which will in all likelyhood just confuse the issue rather than helping solve it but I would bench bleed the M/C (on the vehicle of course) & retry it as the M/C will need to b bled anyhow as a matter of course but as you said most likely a lengthy bubble is downstream by now.
Posted By: GetAwayDriver

Re: Ran Brake Master Cylinder Dry... - 05/01/11 04:30 PM

pads are newer, did them perhaps 6 months ago. Lots of dirt/fluid around the master cylinder cap, so I'm guessing this may be the leak.
Posted By: stumpy

Re: Ran Brake Master Cylinder Dry... - 05/01/11 04:47 PM

A leaky cap won't run the master dry just low. Somewhere you have another leak. It could be the rear master cylinder seal leaking into the booster which is hard to see.
Posted By: wicked

Re: Ran Brake Master Cylinder Dry... - 05/01/11 07:06 PM

Have always had the best luck letting the system gravity bleed moreso than vacuum bleed etc when dealing with ABS, but like others said there is a leak somewhere
Posted By: GetAwayDriver

Re: Ran Brake Master Cylinder Dry... - 05/01/11 07:44 PM

Took the master off, backside looked dry. For the heck of it, I put it back on to see if I could bench-bleed it. I could not seem to get the air out of it.

Friend is off to Autozone in my superior Mopar.

Also looked at the wheel cylinders/calipers/hoses. Everything looks clean and dry.

If it were leaking from the rear and into the booster, I should suspect engine vacuum would draw the fluid into the engine and burn it. This car has been throwing up either an EGR or O2 sensor code for a long time....
Posted By: GetAwayDriver

Re: Ran Brake Master Cylinder Dry... - 05/02/11 02:28 AM

I did solve the problem with a new master and gravity bleeding all four bleeders... (Didn't really take too long) However, if you'd like to read my dangerous Chinese parts story, click here:

https://board.moparts.org/ubbthreads/show...e=0#Post6612694
© 2024 Moparts Forums