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Brakes still applied when my foot is off the pedal

Old 06-02-2018, 05:09 PM
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rickjames8
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Default Brakes still applied when my foot is off the pedal

Hey folks,

So I bought an 87 944 NA in November of 2017, then joined Rennlist in Jan 2018, but haven't posted because I've been able to find all my answers with the search feature, until today.

My 944 is my daily driver, and has been impressive in that role. I have a van that I use for bigger jobs, which forced me to use it for 8 days straight the other week. When I took the 944 back out, I heard a odd noise coming from the brakes. The sound was rotational, in sync with 1 wheel rotation. It was coming from the rear, but hard to tell if it was passenger or drivers side. I got to the end of the block, turned the car around and parked it until I could look at it (today).

I removed one rear wheel, no sign of any rips/tears in the CV boots, no play in the wheel (so bearings should be fine), and the pads were flush against the caliper. However, I noticed quite a mark on the rotor where the rear pads had once sat. It left a mark that I could feel with my finger. So my thought being with all the rain over that week, that I just had buildup on the rotor that needed to be worn off. So I took it for a 15 minute drive, came back home and the sound was no different.

During that drive, I mostly heard the sound at lower speeds, and noticed that it's present when I'm braking and when I'm not. But when I'm braking it changes pitch. When I got home, I parked the car (my driveway is on an incline) and let it roll back. I could hear screeching, and the car was not moving freely, yet the parking brake was off, and the brake pedal was not applied. Applying the pedal to stop the car would stop it, but not before making quite an awful screech.

My first thought is that the parking brake needs to be adjusted back a bit, but the parking brake really only holds the car when it's pulled to the very top. If I let it down just a couple notches, it does nothing. I get the same sound as with the parking brake all the way down.

Not sure what I should try next? Is there a way to release the brakes from being applied a bit? Would this be done at the pedal?

Thanks in advance for any help.
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Old 06-03-2018, 12:44 AM
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mel_t_vin
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Sounds like you may have a pebble/screw/washer trapped between one of your pads and rotors.
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Old 06-03-2018, 01:00 AM
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rickjames8
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Interesting theory. I'll check that tomorrow.

I had another idea tonight. It might be that my parking brake pads are completely worn. This would explain why I need to pull the lever to the highest click. Also, it's possible that with all the rain, the cable rusted up just enough where it's now not retracting fully. And if the pads are worn to the metal, this would explain the screeching noise.

Thoughts?
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Old 06-03-2018, 08:40 AM
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probably just rust. go through the bedding procedure for new pads/rotors and the sound should go away.

used properly, the parking brake shoes should last forever. loosen the cable at the handle and adjust the shoes. tighten the cable until there is drag at three clicks and the forth should hold. test accordingly.
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Old 06-06-2018, 12:38 AM
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KevinGross
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You need to take your car to a mechanic and have someone who understands its brakes check the problem out.
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Old 06-11-2018, 10:29 PM
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The Forgotten On
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Remove the rear caliper and see if anything is jammed in the rear pads. It's an easy 30 minute job.
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Old 06-12-2018, 03:30 AM
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Spring44
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How old are your rubber hoses? Sometimes the inside of the hose will collapse and act as a check valve. This keeps the fluid pressure from fully releasing when you let off the brakes and keeps the caliper piston from properly retracting. Causes a drag on that wheel.
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Old 06-13-2018, 10:15 PM
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rickjames8
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Thanks for all the advice. The rain finally lifted on a day when I had time and I took apart the rear brakes and the problem was half what I suspected.

My theory was that the parking brake was completely gone, causing a metal-to-metal sound. Well, I was half right. One parking brake shoe had broken in half. Judging by the wear, this happened long ago.



Also, the spring looks like it's pushed in to the cog, although looking for other photos on line, this seems to be normal.



Lastly, I can push the whole braking system side by side by a few mm in each direction, which I wouldn't think I'd be able to do.



This is the first car I've had which has had an internal parking brake (that I've needed to work on anyway) so I'm not sure what the norm is here in regards to the movement. I've ordered new pads and will install them this weekend. I'm pretty confident that will fix the problem,
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Old 06-13-2018, 10:18 PM
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Oops, looks like I transposed photo 2 and 3 - they're with the wrong caption.

Also, I used my image hoster, but only because I tried uploading the photos and they looked massive, regardless of how I resized them. Is that normal?
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Old 06-13-2018, 11:11 PM
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Spring44
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The long spring needs to be pushed into the toothed wheel to keep it from rotating. The toothed wheel is the brake shoe adjusting mechanism and you wouldn't want it to be able to turn freely after you have adjusted the brakes.

As to back and forth movement, the brake shoes are held in place by pins and springs, so some movement is normal with the drum off. Missing chunks of brake lining are not normal.
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