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Posted by: 914itis Apr 15 2017, 12:07 PM

I replaced my lines , and trying to bleed the brakes .
Using regular dot3 brake fluid.

No matter what I do , I have to hit the pedal three -4 times before it gets hard .
I bled them over and over , same result. I tried bleeding them using the old method , pump until hard then unscrew the valve until the pedal hits the floor , screw back as the pedal is pressed / repeat .
I started from the back right , then back left then front right and front left.
I also tried using the vacuum bleeder at HF. Same result.

Posted by: mgphoto Apr 15 2017, 02:07 PM

Air in your brake bias valve, "proportion valve " call it what you will.
Located behind the driver on the firewall in the lower engine compartment, it is the highest part of the brake system.
With a helper, pump up the brakes, crack each of the fittings while under pedal pressure. Do both fittings, cover with a rag or it will spray brake fluid.
Mike

ps: power bleeder is best.

Posted by: Perry Kiehl Apr 15 2017, 02:31 PM

http://www.914world.com/bbs2/index.php?showtopic=297230&hl=brake+bleeding

Posted by: 914itis Apr 15 2017, 04:18 PM

there is no proportioning valve, Just a Tee

Posted by: Kansas 914 Apr 17 2017, 09:11 AM

QUOTE(914itis @ Apr 15 2017, 04:18 PM)

Posted by: Racer Chris Apr 17 2017, 09:14 AM

QUOTE(mgphoto @ Apr 15 2017, 04:07 PM)

Posted by: worn Apr 17 2017, 09:38 AM

QUOTE(914itis @ Apr 15 2017, 10:07 AM)

Posted by: Andyrew Apr 17 2017, 10:08 AM

Have you tried hitting the master cylinder and brake calipers with a hammer to burp the bubbles out?


Also how did you do the rears? Did you adjust the pads correctly in the rears?

Posted by: 914itis Apr 17 2017, 10:18 AM

Pad is adjusted correctly , I used pmb's method , went for a drive . I did'nt give it a try again after the drive, I will today. .

Posted by: Racer Chris Apr 17 2017, 10:25 AM

Sometimes old MCs fail during brake bleed, especially if the pedal is bottomed out while pushing the fluid out.
The seal gets nicked as it passes the opening to the reservoir and never holds pressure well again.
I've even seen it happen with new MCs.

Another common cause of a long pedal is freshly rebuilt calipers. the new seals grab the pistons hard enough that they don't auto-adjust at first, so on release they back away from the rotor enough to require extra pumping.

Posted by: McMark Apr 17 2017, 11:46 AM

You probably allowed air into your MC. It's a bitch to get back out again. To do this reliably, I've always had to plug all the lines in the MC, then pump the pedal until the pedal gets 100% solid. Then reconnect the rear/front right/front left in that order. Bleeding each circuit as it's added. This has the side benefit of illuminating exactly where a problem might be as well. If you add in the rear circuit and suddenly can't get a firm pedal anymore, your problem is probably in the rear.

Another brake system tip: if you keep the pedal depressed when you replace components, your reservoir won't drain AND you won't allow the MC to fill up with air. Do this while you remove the plugs and reinstall the hard lines so you don't loose the work you did to bleed the MC.