Brake squeel

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Kyle Wolfe
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Joined: Mon Mar 17, 2003 12:30 am

Brake squeel

Post by Kyle Wolfe »

I've got a brake that's driving me crazy. Makes a squeeling noise. Goes REEK, REEK, REEK as the tire rotates. As soon as I apply a bit of brake the noise goes away.

I had my A&P put new pads and rotors on at last annual approx. 50 hours ago. Brakes work just fine.

I have solid brake lines and plan to put the flexible ends on and replace the upper end of the line. Will also look closely at the brakes at that time.

Someone told me that I'm likely getting brake chatter and squeel from the solid lines not causing the caliper to float freely. I'm guessing that I've got either a warped rotor or just glazed pads.

Thoughts from the group?
Kyle
54 B N1932C
57 BMW Isetta
Best original 170B - Dearborn, MI 2005
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ravenaviation
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Post by ravenaviation »

A few thoughts for you:

1. The pins that hold the caliper could be binding a little. It might be a good idea to pull it apart and clean the holes and the pins real good with scotch brite. When you reassemble them it might help to use some of that silver anti-seize on them. It doesn't seem to pick up dirt and grit so bad.

2. When you did the pads, did you replace the seals on the pucks? That might be a good idea. Also have a look at the well they go into to see if it is scored. Those seals can get flats on them.

3. Did you bleed the fluid from the brakes? If it is not bright red like new fluid, I would think you might want to drain it all and replace it. That stuff can get pretty bad after a while. It gets a pale orange color and starts to thicken.

4. You can check for rotor alignment by just jacking and spinning the wheel slowly and seeing if it wobbles. You could make a measurement from a place on the strut to the rotor as a guide.

5. The flexible ends might help, I don't really have any knowledge of that.

6. At risk of my sounding stupid, are you sure you got the bearings seated when you put the wheels back on? You might want to check for wobble (jack it and wiggle them).

7. Maybe you could just grease the rotor face, that would stop the squealing. (Just kidding, honest!).
John
LaPorte, TX (T41)
N2363D, Cessna 170B
zero.one.victor
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Post by zero.one.victor »

I had some brake squeaking that annoyed me during taxiing, especially apparent if I wasn't wearing my headset. I got rid of it by cleaning & lubing the pins that the brake calipers float on (see #1 of John's post). I didn't use anti-sieze, just WD40 or maybe LPS heavyduty spray lube. I've repeated the clean/lube treatment a couple times, when the squeaking reappears. The solid brake lines might contribute to the squeaking also.

Eric
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GAHorn
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Post by GAHorn »

I use a gun-cleaning bore-brush to clean out those pin-holes and then lightly grease the pins with marine water-proof wheel-bearing grease (the same stuff I use on my wheel bearings.) Solves the problem of binding brake calipers.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Kyle Wolfe
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Post by Kyle Wolfe »

Thanks guys for the tips. Think we found our problem. We pulled stuff apart today and it seems like there's too much free play. So we ordered new pins and backing plates.

We still plan to put the flexible ends on the lines as well. Any specifics on how long the flexible line should be? I've searched the site but not found specifics. From what I can tell they should be 9" - 12", correct?
Kyle
54 B N1932C
57 BMW Isetta
Best original 170B - Dearborn, MI 2005
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GAHorn
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Post by GAHorn »

Sounds good, Ken. Try to align the hose with the trailing edge of your gearleg to avoid unnecessary drag and tall grass strikes. :wink:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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