Hot Brake Drum

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cheezsnake

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1971 Mustang, 351C 4V
Over the last few weeks, I overhauled the brakes, including new drums, shoes, cylinders in the rear, and an aftermarket disc upgrade in the front. Took it for first test drive yesterday ... actually first time I've been able to get it on the road this year. Made sure that I had a good brake pedal before heading down the road. Took it easy. Car ran well. Stopped fine. Avoided any hard stops for now. Exhaust has a good tone, but I didn't notice any odd noises, shuddering, pulling to one side or the other. Car rolled freely with the clutch in. Ended up being about 20-30 mile trip.

When I pulled back in the garage and got out of the car, I noticed a hot smell. I walked around the car, and when I got to the right rear wheel, I could feel the heat coming from it. Let it cool a little while. Then, decided to use a temp gun. That wheel was still 30-40 degrees warmer than the others. Jacked the car up and removed the rear wheels and drums. I was surprised the right drum came right off. Was expecting it to be frozen up. But, that drum was discolored, dark and blue, compared to the left drum. I put a caliper on the shoes, and in that 20 mile trip, the new right shoes had lost a good 1/16 more than the left side.

I must not have had the right side shoes adjusted correctly. Will need to get the drum checked or replaced, and readjust the brakes. What I don't get is how it seemed to drive just fine, and how that drum came right off? Am I missing something?
 
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Did you check the backing plates for wear? Specifically, the raised areas that the shoes rub against. If these are badly worn, or worn through, they can hold the shoes against the drums. They also need a smear of high temperature grease on them.
 

cheezsnake

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I did put hi-temp grease on those raised areas. It didn't occur to me to check those plates for replacement, though. None of them were worn through, but I recall some were not exactly flat/smooth. Don't remember which spots or on which side of the car.
 
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I hate rear brakes, been my nemesis for years. But one thought, did you get the leading shoe on correctly. Or is the parking brake adjusted correctly.
It seems like you have a good understanding of how these work, probably more than do I, but sometimes, it's the simplest mistakes that get us. Ask me how I know.
 
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I am going to give a stab at this. When you did your rear brakes did you get the self adjuster repair kit? Not everyone buys the self adjuster repair kit, but they probably should. The self adjuster cables stretch and end up not working correctly, and it is very difficult to tell just by looking if yours are a little stretched, and the self adjusters when old sometimes do not move very freely. You can usually clean the self adjusters and lube them and get them working pretty good, but if the cable is stretched they need to be replaced. The other thing that can happen is that the self adjusters are not the same, one goes to the left and one goes to the right, if you invert them, they will not work. The self adjusters are usually marked with an L and a R on them, so you know to which side they go.
The other thing is that after you do your rear brakes you should go in reverse and brake a couple of times and use your emergency brake a couple of times so that the rear brakes self adjust. When you do your rear brakes you only get the drum to shoe adjustment close, then you get in the car go in reverse and brake a couple of times, then go forward, and then use your e-brake a couple of times so that your self adjusters adjust the brakes. ( I can't recall if our cars adjust when going in reverse or when the e-brake is used so just do both). Only thing I can think of is that you adjusted the rear right a bit too tight, and just ran the car. That side may not be self adjusting because of a stretched cable or the adjuster may be the incorrect one, you may have a left side adjuster on your right side, which will not let the system adjust. I would think that if everything looks good, except for the wear on the shoes, that you should be able to just use everything again.
 
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I am going to give a stab at this. When you did your rear brakes did you get the self adjuster repair kit? Not everyone buys the self adjuster repair kit, but they probably should. The self adjuster cables stretch and end up not working correctly, and it is very difficult to tell just by looking if yours are a little stretched, and the self adjusters when old sometimes do not move very freely. You can usually clean the self adjusters and lube them and get them working pretty good, but if the cable is stretched they need to be replaced. The other thing that can happen is that the self adjusters are not the same, one goes to the left and one goes to the right, if you invert them, they will not work. The self adjusters are usually marked with an L and a R on them, so you know to which side they go.
The other thing is that after you do your rear brakes you should go in reverse and brake a couple of times and use your emergency brake a couple of times so that the rear brakes self adjust. When you do your rear brakes you only get the drum to shoe adjustment close, then you get in the car go in reverse and brake a couple of times, then go forward, and then use your e-brake a couple of times so that your self adjusters adjust the brakes. ( I can't recall if our cars adjust when going in reverse or when the e-brake is used so just do both). Only thing I can think of is that you adjusted the rear right a bit too tight, and just ran the car. That side may not be self adjusting because of a stretched cable or the adjuster may be the incorrect one, you may have a left side adjuster on your right side, which will not let the system adjust. I would think that if everything looks good, except for the wear on the shoes, that you should be able to just use everything again.
Good point, the self adjusters have left and right thread, so must be installed on the correct corresponding side. I too think they are marked for which side of the car they go.
I've never used the "parking brake" for adjustment. After initial adjustment through the oblong hole, I just back up and hit the brake hard a couple of times.
One other thing that now comes to mind, is when I did my brakes a year or so back, I got one of the bottom springs on wrong, which was pointed out by a member. I was posting about a slight rear axle seal leak and posted a pic of that.
If it were me, I'd just go back, strip it all out and redo it.
 

Superbond

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Stanglover’s right.
I too had leaking seals and redid my brakes with all new parts. And I too had brake issues. Back brake drums got up to 440 degrees.
Posted pics of my brake job and a member pointed out the cable was in behind where it was supposed to be and stuck. I changed that and new adjusters and everything was good.
And yes the height spots on the backing plates were worn and would make my brakes stick. So I welded them them ground them smooth. Then added grease and all was good
 
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