aam993

Decided to flush brake fluid, connected empty bleeder, pumped to 10 psi, everything was good - pressure was holding steady, nothing was leaking. Then depressurized the bleeder, added brake fluid, put the cap back on and - the air comes out from the pumping shaft - no pressure can be built.
Has anybody had such problem? Is it common to all pumps? Is it just a matter of lubing the shaft with the oil? If yes, which oil can I use? I saw cautions on not using petroleum-based oils, only "brake fluid"-compatible oils - what are they?

I drained brake fluid back into the container from bleeder and closed it tightly - is it alright to still use it tomorrow or day after tomorrow? I know that brake fluid absorbs the water very quickly.

Thanks!

Ray Calvo

I can't offer much help except try to find a site for the bleeder manufacturer and ask them. AS far as trying lubricating oils, I would say try the brake fluid itself. If it won't damage master/slave cylinders, don't think it would damge the pump piston.

I use fluid from previously opened containers frequently; no problems. Closing the screw top should be similar to the original sealed top on the container.

aam993

Thanks, Ray. I will be exchanging this bleeder for a new one - bestforeignparts.com told me that it's not a problem. I also thought about using brake fluid as a lubricator, but actually brake fluid comes around the middle shaft(same way air goes out), so it must be something more serious than just lubrication.

Meanwhile, this turned out for good - I'm going to introduce my wife to Porsche - I've asked her to help me with flusing brake fluid(pushing brake pedal) and she agreed. "Push-hold-release"!

kkim

Getting the wife introduced to the Porsche is a great idea, using the "push-hold-release" method to bleed the brakes may not.

Many times (in other cars that I have owned), after using this method, brake master cylinder problems can occur. I would wait for the new power bleeder to arrive instead of chancing potential problems.

Good luck

aam993

Does it happen from pushing brake pedal too far? I've seen suggestions to put wood block behind pedal.

Thank you for the adivce! For some reason I've got an impression that manual bleeding (with an assistant) is still preferred by some people - even with power bleeders available - therefore I though it is a safe method...

kkim

Alex,

Yes, it is from pushing the pedal beyond it's normal travel and possibly ripping the seals in the cylinder bore due to corrosion/rust that might be in there.

I've used the "wood block behind the pedal" method on other cars and it worked without resulting MC damage. I would strongly suggest that if you go the "push-hold-release" method to use a wood block behind the pedal to limit the pedal travel to it's normal brake usage stroke length.

Rezal

Late 95s cars and onwards such as yours had the brake reservoir overfill hose crimped. Mine's an early 95 that requires me to vice grip the hose to hold pressure. Check to see if you overfill connection is still airtight. Just a shot in the dark but who knows?

Greg Fishman

Make sure the O-ring is in the pump part of the bleeder so it has a tight fit. My bleeder had this ring crimped or not set right and it wouldn't hold pressure, once fixed it was back to normal.

aam993

Greg, yes - that's sounds like it. But how do you take the pump apart? I looked at it and tried to understand how it is put together and could not figure it out. Thanks!

amfp

Is is Late 95's that you need the vice grip to hold pressure ? Or is is 96's on ? Is there a way to check without having the fluid spill out ? Thx.

Greg Fishman

The o-ring (or at least a o-ring) should fit around the pump mechanism so it fits flush and tight to the bottle portion. I didn't get inside the actual pump mechanism.

aam993

Ok, I understand. Unfortunately it's not the problem.
Well, the power bleeder goes back to the seller today. Hopefully replacement won't take long to arrive back because I will need one - tried to manually bleed brakes and every "pump-hold" cycle was producing only ten-twenty drops of fluid. That was with wood block behind brake pedal - it was at the point where brake pedal normally stops. It took ten minutes to get just couple ounces of old brake fluid bled.
So, I decided to wait until working power bleeder arrives.

Thanks for your help!

nile13

Alex, I had a very similar issue with the first Motive bleeder I ordered. It would not hold pressure. Had to have it replaced.
I since gave up on this method of bleeding and bleed all my cars by pump-hold method (I also have SpeedBleeders installed in the race car, but still use pump and hold). Just a personal preference, although I have not blead P-car's brakes yet.

PS. I think I know you from before? Mike.S

aam993

Yes, Mike, from r.z1.
Thanks for letting me know that I'm not the only one with Motive bleeder problems. While searching on inet, I saw only praises to how good that thing is. Well, it's true when it works. Truly makes brake bleeding quick and easy.
Why did you give up on pressure bleeding?