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Jerry
06-08-2014, 10:11 PM
I asked this question once before but I have more info now:
Rear brakes put pressure on but not enough to really slow the car. I had the adjustment on the rear wheels so they were one notch below lock on the wheel. So when driving the car, the lack of pressure causing loud vibration when coming to a stop. The drums have just been turned. If I put the emergency brake on about 4-5 clicks, the vibration goes away and the pedal engages higher also.

So, either the shoes are not fitting the drums well, or the rear restrictor is limiting the brake fluid to the back. By the way that restrictor was taken out and cleaned when I replaced all the brake parts.

So any ideas?

Jerry
TR3A
New master, new rear cylinders, rebuilt front calipers.

TomMull
06-09-2014, 07:47 AM
I might try re adjusting the rears a couple of time after driving the car so everything has a chance to set. If the brake drums have just been turned, the new radius will not quite match the shoes, so some wear in will be necessary. When I worked on trucks a half century ago, we would send the shoes out to have them "radiused" with the newly turned drums. That was usually not required with cars but a considerable wear in time would be expected. I'd also mention that the quality of drum turning seems to be quite varied and I try to use new ones instead.
Tom

Jerry
06-09-2014, 10:55 AM
What about adjusting the emergency brake cable to pull in some of the slack? Seems like that would be the same as adjusting the brakes up tight.
Jerry

TomMull
06-09-2014, 05:25 PM
What about adjusting the emergency brake cable to pull in some of the slack? Seems like that would be the same as adjusting the brakes up tight.
Jerry

Kind of like permanently pulling the lever a couple of notches. I'm responsible for many such "fixes" but in this case I'd rather find and fix the problem. Parking brake should be adjusted after the main shoe adjustment.
Another thought: Are the shoes oriented properly? I think yours are directional.
Tom

TFB
06-09-2014, 05:32 PM
I asked this question once before but I have more info now:
Rear brakes put pressure on but not enough to really slow the car. I had the adjustment on the rear wheels so they were one notch below lock on the wheel. So when driving the car, the lack of pressure causing loud vibration when coming to a stop. The drums have just been turned. If I put the emergency brake on about 4-5 clicks, the vibration goes away and the pedal engages higher also.

So, either the shoes are not fitting the drums well, or the rear restrictor is limiting the brake fluid to the back. By the way that restrictor was taken out and cleaned when I replaced all the brake parts.

So any ideas?

Jerry
TR3A
New master, new rear cylinders, rebuilt front calipers.

Im guesing you have taken the drum off for inspection.Im going thru the same thing and my problem seems to be shoes that came with project that looked new must be oil soaked.I have tried cleaning and each time after a short run there is a gummy build up on shoes,no hydraulic leaks or oil from axle.Just a thought to pull drum before adjusting anything.I need new shoes.
Tom

Jerry
06-09-2014, 10:59 PM
Well, I have new shoes but I did not know they were directional. Can you give out more info on that?
Jerry

TomMull
06-11-2014, 10:18 AM
Well, I have new shoes but I did not know they were directional. Can you give out more info on that?
Jerry

Sorry no picture but here's the best I can do. There is a good picture in the factory service manual TR3 supplement page 4 of the brakes section.
The lining is not centered in the shoe itself. The shoe that goes onto the cylinder piston is placed so that the area where the lining does not go to the end of the shoe fits into the cylinder piston. The other shoe is opposite.
Hope this helps.
Tom

Jerry
06-11-2014, 10:21 AM
Thanks Tom. I have the service manual but never looked at for the brakes since my brain said they were the same as other brakes. I will look at that issue first.

Jerry

sp53
06-13-2014, 10:48 AM
Something sounds incorrect here. Maybe a rear wheel cylinder is loose and perhaps some air still in the line. The way those cylinders attach is tricky with those 3 little clips. They have to go on in a certain sequence or the cylinder will float. Truth is I think they float little anyway, but if they float too much they would give the problem you describe.

TR3driver
06-22-2014, 07:08 AM
Have you checked the hose to the rear axle? I've had them break internally and block the flow of fluid, even though the outside looked OK.

As noted, you really don't want to be using the e-brake cable as a substitute adjustment; except maybe on a very temporary "limp home" arrangement.

The "loud vibration" sounds suspect too. Even badly out of adjustment and only partially applied, the rear brakes shouldn't vibrate. Which brakes do you have? If they are the ones with no hold down springs and adjustable rests, the rests may not be adjusted properly.

Jerry
07-12-2014, 10:08 PM
Just wanted to give you an update. After putting a few hundred miles on the car, the pads have worn in and I can adjust them to the drum. I also was able to adjust the emergency brake better. It would be nice if someone around here still fit shoes to the drum.

Jerry

TR3driver
07-16-2014, 07:27 PM
I saw one of those machines come up on Ebay a few years back. Decided I didn't have any place to keep it (and didn't want to pay the shipping). Or, it wouldn't be all that hard to make one yourself. Just a disc sander with an adjustable, pivoting platform to hold the shoe.