Chunkerz

I'm attempting to bleed my brakes, but my power bleeder isn't working. I sucked out the old fluid with a Mighty Vac, poured new fluid into the reservoir/power bleeder, pumped it up to 10 psi, then cracked the bleeder on the right rear wheel, but nothing came out. No air bubbles, no old fluid, absolutely nothing. I put my Mighty Vac on the bleeder valve and tried sucking the fluid out but that didn't work either.

I gave up on that wheel and tried the left rear wheel just to see if anything would come out. Nothing came out. I tried the front left wheel and nothing came out again. I tried the front right wheel and fluid came gushing out, so is it possible the lines going from the master cylinder to the other 3 calipers are clogged? I recently replaced my pads, rotors, and the rubber brake lines with stainless steel lines from 944 Online. The brakes worked fine when I took the calipers/old brake lines off and I didn't leave the brake fluid reservoir open while my car was down over the winter so crap shouldn't have been able to get in there.

What should I check next? Remove/clean the reservoir? Replace the master cylinder? Use an air compressor and blow air through the lines to unclog them? New brake lines are uber expensive and look like a bitch to replace, so I'd really rather not go that route...

Arominus

Do not apply shop air to your brake lines at high pressure! I would pull the new hoses and see if you get flow to the caliper, if not then I would pull the flex line at the hard line, and check for flow. That will isolate your problem area. Use your mity to check, as will be faster than the pressure bleeder.

jeffrsmith

I had a similar issue with mine when I replaced the brake hoses, there was corrosion in the bleeders; I was not able to get anything when trying to bleed the brakes, but when I took the bleeder screw out completely the fluid flowed from the caliper. I blew out the bleeder with shop air, put it back, and was able to bleed the calipers normally - the rubber bleeder covers are there for a reason, mine were missing.

abarthel

I also had this same problem with my power bleeder. A quick step on the brakes while the motive is pressurized to about 10 PSI. and the bleeder screw loose, broke free any crap that was blocking the bleeder screw.

John_AZ

Example of possible "crap" in the caliper-credit to member exitwound



J_AZ

Gawernator

Yep.... and to help clean out the system try bleeding with some denatured alcohol.

Chunkerz

Is it safe to put pressurized air in there at all? Something super low like 10psi? I disconnected the flex line from the hard line for the right rear caliper and nothing came out. I did the same for the front left and fluid came dribbling out. I haven't tried the left rear yet.

I tried it without the bleeders to no avail.

I tried this earlier and it didn't work

Damn. I should have rebuilt my calipers while I had them off
Edit- brake caliper rebuild kits are on the way. Hopefully all it is is clogged calipers and not FUBAR'd brake lines...

I'll see if I can pick some up tomorrow.

Arominus

I'd be concerned about clogging it up more... Have you done the traditional bleed? (2people pump and bleed)

Chunkerz

Not yet. I'll see if I can get a friend to stop by tomorrow.

Gawernator

Hmm... You are using vacuum and not pressure. I highly recommend getting a Motive /pressure/ bleeder for future use anyways... maybe he Motive plus pumping the pedal would do the trick. I bleed mine around 10 PSI too

Chunkerz

I am using a Motive Power Bleeder. After the Power Bleeder alone didn't do ****, I added vacuum. I'm not sure why. I saw my Mighty Vac sitting there so I just grabbed it.... I stepped on the brake pedal a few times with the Power Bleeder hooked up and nothing is coming out. I am getting fluid from the front left caliper now, but both rear calipers are still dry. I disconnected the stainless steel line from the hard line that comes from the master cylinder for both rear calipers and there's no hint of brake fluid. I'll try disconnecting the line from the master cylinder to see if the brake line or the master cylinder itself is clogged tomorrow.

Which lines on the master cylinder go to the rear calipers?

Gawernator

Strange... was your fluid not changed for a long time or something? I think the denatured alcohol might help a noticeable amount

Van

As I think you've figured out, your Motive bleeder is working fine... something else is the problem.

I would systematically, remove all brake line connections and blow each line out with compressed air. What you don't want to pressurize at shop pressure is the reservoir - it'll burst. All of the other components are rated for at least 3,000 psi.

I have a hunch that you're going to be amazed by the braking of your car when you get this all fixed!

p.s. you can always buy straight brake line segments and bend them up yourself. Just be aware that the fittings on the ends are metric...

Chunkerz

I'll give that a try today. I think I figured out which line goes to the rear of the car. It's the one closest to the front of the car that goes to the 3 way T just above the torsion bar housing, right?

Arominus

Thanks for the specifics van, when I posted my warning I had visions of blown out rubber seals in the res. I should have been more specific.