TR2/3/3A TR3 brake [?] squeak

[NutmegCT]

I drove TeeYah down to Long Island Sound a few days ago. What a great drive - about 180 mi r/t, all along our New England secondary roads through forests, meadows, farmland, villages, six-car ferry across the Connecticut river, etc. Got lots of waves and "what a neat car!" comments at every town, and the driver of an older two-tone Harley saluted me! TR ran perfectly far as I can tell; not a hiccup, lots of torque, oil and temp normal the whole way.

On the way home I noticed a slight "squeak" coming from the right front wheel. Just a little "on and off" chirp, which varied with the wheel speed.

Squeak would completely stop when I just barely touched the brake pedal.

What are "the usual suspects"?

Thanks.
Tom

 

[NickMorgan]

My cure would be to the brake pads out cleaned everything and check that the caliper piston is free. Then put a very thin smear of copper grease on the back of the pads and put it all back together. Then drive your lovely 180 mile trip again just to be sure that the problem is cured!
Your journey sounded great. Last week I took my TR3 up to a business meeting in Perth. Sadly most of the 160 mile drive was on motorways and smoothest speed seemed to be 80mph, but I still passed an old Mini, an early Morris Minor, a Bristol and an MGB GT. I enjoy driving over the Forth Road Bridge and looking up at the structure. It was also good to receive mileage from my work!

 

[NutmegCT]

Thanks Nick. I hadn't even thought it could be the pads, as they only have about 500 miles on them and didn't squeal until this trip.

I agree on "looking up at the structure". In my case, it was several canopies of oak and hemlock trees. But a Scottish bridge would be high on my list!

Tom

 

[TR3driver]

While Nick's suggestions are sound, the intermittent squeak also indicates that there is some runout in the brake disc. You might want to check it while you're in there.

 

[PSUTR3B]

I had the same problem after finishing my TR3B. The brakes were about the last thing I did and after several miles the squealing started when stopping and seemed to get worse. I took the front brakes apart and cleaned them-took the shims out and then put them back and no relief. I finally took it to a LBC mechanic who took the restrictor valve out and no more squealing. Several thousnd miles later and still no squealing and no problems with brakes without the restrictor valve. I seem to remember a thread some time ago about removing the restrictor valve without causing braking problems.

Perhaps others have had the same result.

Gary

 

[TR3driver]

I seem to remember a thread some time ago about removing the restrictor valve without causing braking problems.

Well, the problem it was intended to solve seems real to me; but it won't manifest if you don't drive the car hard.

What happens is that in hard turns, the front spindles flex a bit. Without the residual pressure valve, when the spindle flexes, the brake disc pushes the pad back into the caliper, resulting in a low pedal next time you apply the brakes.

But I disabled my RPV many years ago, and I can't say the low pedal has ever been a problem. It's just something that would be scary, if you didn't expect it.

 

[NutmegCT]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:] The brakes were about the last thing I did and after several miles the squealing started when stopping...[/QUOTE]

Just to clarify - I've been driving for over a year without any squeal/squeak. It was this long trip that seems to have kicked Mr. Squeaky into gear.

The squeak is repetitive, and occurs as the wheel is rotating. Like one little "peep" for every rotation of the wheel. Faster you go, faster the "peep".

Just barely touch the brake pedal, the "peep" goes away. Remove foot from brake pedal, peep returns.

I first thought it might be a failing wheel bearing, but the brake pedal "cure" would nullify that theory, (right?).

Thanks.
Tom

 

[Brooklands]

Nick,
Would one of these be your Firth Road Bridge? They are from my slides I took back in 1976 on holiday...

 

[70herald]

The first picture would be the Firth of Forth Railway bridge.

Presumably Nick drove across the second bridge.

 

[angelfj1]

Not sure but I believe Nick is referring to Perth, Scotland! Perth is due north of Edinburgh on the M90. Been there - very lovely country!

 

[NickMorgan]

That's the one (the second one!) The railway bridge has scaffolding and tarps all over it at the moment. They seem to be painting it, which is not unusual as they are always doing that!

Tom,
My thought with your brakes was that your discs are slightly out of true and they are rubbing the pads to varying degrees. Your squeak may be sort of high frequency vibration caused as the discs rub past the pads. The copper grease absorbs the squeak.

 

[bgbassplyr]

Try pulling the pads and put a bevel (maybe 1/8-1/4" wide) on the leading edge. What may be happening is a vibration between the disk and pad, much as a bow across violin string. Bevel will keep the pad from hitting the disk at the angle required for squeel.

 

[Brooklands]

The first picture would be the Firth of Forth Railway bridge.

Thanks...my remembering after 33 years is not always the sharpest, but I knew my photos were from my hotel along the Firth of Forth for one night during the US Bicentennial year.

Now I will stop stealing Tom's topic.

 

[NutmegCT]

Try pulling the pads and put a bevel (maybe 1/8-1/4" wide) on the leading edge. What may be happening is a vibration between the disk and pad, much as a bow across violin string. Bevel will keep the pad from hitting the disk at the angle required for squeel.

Jim - the squeak is like a "chirp" that happens once per revolution of the wheel. And of course, it only happens after the car has been driven a while - never when cold.

I notice all the suggestions relate to the brake, and not the wheel itself. So can I safely (!) rule out a wheel bearing problem?

Edit: I've only got one free day this week (Thursday), so I want to get the job done without spinning my wheels too much - no pun intended!

Thanks.
Tom

 

[bgbassplyr]

Nut,

I was led to the brakes because they are relatively new (500 miles), the chirp/squeek occurrs once per revolution, and stops when the brake pedal is touched.

You did not specify what type of wheels you have. If wires, check for loose spoke(s). If steel, check for loose wheel nuts, bent or warpped wheel hitting top ball joint or other suspension componet.

If loose wheel brg., jack the car and check by rocking wheel back and forth with hands in the 12 and 6 o'clock position. You can also pull wheel brg. cap to check for grease on the outer brg. If the wheel rocks in 12/6 test, you may be able to see the brg rocking.

If you have gone this far with nothing obvious, pop the cotter key out and check the axle nut for loose condititon. Tighten the nut till brearings are seated (wheel rotation is 'tight'), back off one flat and reinstall the cotter pin, (check the manual for this procedure).

If you have beveled the pads and all the other tests proved negative, and the chirp is still present, you may want to look to others for advice as I'm pretty much out of answers on this one.