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TR4
06-19-2007, 09:39 AM
I set the rear brake adjusters last summer and now the rear brakes are hanging up. I took a short run yesterday and the wheels got very hot. Checked the handbrake cables and those were loose and not binding anywhere. I reset the adjusters so the wheels turn free now but what would cause the brakes to self adjust to way too tight? I have new wheel cylinders on the bench so could change those out if needed. Advice is appreciated.

Paul Johnson
06-19-2007, 09:44 AM
Double check a parts catalog to be sure you have the adjusters on the correct side and installed the right way.

Sounds like you have the adjusters in backwards, causing them to tighten as you drive forward.

Andrew Mace
06-19-2007, 10:36 AM
...Sounds like you have the adjusters in backwards, causing them to tighten as you drive forward. Huh? I didn't think that the adjusters were "sided"; nor can I figure out how they might fit more than one way on the backing plate!

I would make sure that the emergency brake cable and linkage bits aren't hanging up or binding anywhere, and I'd make sure that the wheel cylinder is also free to slide back and forth as it should. I'd also inspect the rubber brake hose to make sure it isn't possibly breaking down internally; this can lead to a sort of "check valve" effect, prohibiting the fluid from retracting after the pedal is released.

TR4
06-19-2007, 10:53 AM
That is correct, my wheel cylinders are not sided and can only be installed one way. I will again check the handbrake cables and see if I have a section of rubber hose on the brake line. I don't remember seeing any rubber hose. I'll probably go ahead and change the wheel cylinders. Any tricks or helpful advice changing those?

Andrew Mace
06-19-2007, 11:56 AM
There will be a rubber brake hose connecting to the pipes on the rear axle (assuming this is a solid-axle TR4). I don't have any special "tricks" for changing wheel cylinders except to a: make sure you study how the retaining clips come off, and get them back on the same way; and b: make sure the backing plate is clean and use a bit of lubrication (I like white lithium grease) to ensure that they will slide freely once in place.

NickMorgan
06-19-2007, 12:13 PM
If the car has been stored in a damp garage over the winter the shoes could have swollen slightly. You could also have a layer of rust on the inside of the drums. I bet you will need to adjust the brakes again after a few days of driving!

TR3driver
06-19-2007, 12:39 PM
I'd also inspect the rubber brake hose to make sure it isn't possibly breaking down internally; this can lead to a sort of "check valve" effect, prohibiting the fluid from retracting after the pedal is released.
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On a TR4, there is only one hose for the rear brakes, and it runs between the hard line on the body and the tee fitting mounted to the rear axle. Has to be there to allow for rear axle movement !

However, it's not always obvious when the hose has a problem. The original hose on my TR3A didn't look bad at all (except for some minor "weather checking"), but turned out to be the problem. It would make the rear brakes drag for a few minutes every time I used the pedal, but would eventually bleed down and they would turn freely again. The return pressure is a lot lower than the "apply" pressure.

Bob_Muzio
06-19-2007, 05:39 PM
On a car that is used infrequently the interior of the flexible brake line might swell, however that generally causes a pull.
I did experience the right rear brake binding on my TR4, adjusted it till it was free and then it bound again as soon as I lowered the car. I replaced both rear wheel cylinders and that corrected the concern.
Bob