# Front drum brake locking?



## Artfuldodger (Jan 29, 2019)

My brother has a 57 Chevy Belair. He says he started having trouble with the front passenger brake locking up. Pretty common complaint for older cars, especially with all drums.
Anyway he installs all four rebuilt wheel cylinders and brake pads, and the front rubber hoses. He bled all the old brake fluid out and has bled the air out multiple times.

The internet says it may be the master cylinder, weak brake pad springs, warped drum, or a bad wheel bearing.

The kicker is a brake man came over and sprayed a whole can of brake cleaner on this one wheel's brake workings. They put it all back together and with just rolling the car forward a few feet made it lock up.

So in relation to this, and not even applying the brake? I'm thinking a warped drum. My brother says the bearings seem OK, no play or noise.

Now could a weak pad return spring cause thins? I don't think so. Maybe if you applied the brake and it had a week pad return spring, but just rolling the car?

The brake guy didn't have any suggestions. My brother has named the car Christine.

One suggestion is to swap the brake drum to another wheel to see if it's the drum. I may suggest that idea.

Anyone have any suggestions or input?


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## transfixer (Jan 29, 2019)

They need to make sure its actually that wheel causing it,  by rolling the wheel with it suspended by a jack or jackstand,  if the brake pedal was never pushed and it locked up it sounds like the shoes adjusted too tight, or brake hardware not installed correctly?    if it only locks up after hitting the brake pedal it could be the equalizer/splitter ,  which is usually mounted on the frame somewhere,  he also needs to make sure the inside of the drums are in good shape,  no rust, no inner ridge which could cause the shoes to drag or grab.


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## Mr Bya Lungshot (Jan 29, 2019)

^^^nailed it!


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## Artfuldodger (Jan 29, 2019)

transfixer said:


> They need to make sure its actually that wheel causing it,  by rolling the wheel with it suspended by a jack or jackstand,  if the brake pedal was never pushed and it locked up it sounds like the shoes adjusted too tight, or brake hardware not installed correctly?    if it only locks up after hitting the brake pedal it could be the equalizer/splitter ,  which is usually mounted on the frame somewhere,  he also needs to make sure the inside of the drums are in good shape,  no rust, no inner ridge which could cause the shoes to drag or grab.



It doesn't have any type of equalizer proportional valve other than what Chevy calls a "block." This is more or less a "tee" as what an all drum brake car has. They use bigger brakes on the front vs the back for equalization. I guess it's possible a passage in that block/tee may be stopped up.
As you suggest, I could see this if applying the brake made it locked up but not pushing/rolling the car.

I'm with you on the drum though. The problem occurred before any work though. The brakes had worked fine for years before. I guess installing something wrong could show up even after years of working properly. I did read about people installing the longer or shorter shoes wrong.

I'll have to get him to spin the wheel while jacked up vs rolling the car. That may help pinpoint something. If it's related to that it seems like it would have to be the drum or wheel bearing. If it would spin free while jacked vs locking up while rolling/pushing.

Weird to think it's equalizer or other brake component as being the culprit if it locks up without even applying the brake. I'd think a wheel bearing would have to be really loose to cause a problem like this.
I'd think that would show up in steering.

It did lock up while just rolling the car on the ground. I don't think they tried to see if it would lock up by spinning the wheel while jacked up. They may have. I'll ask tomorrow.


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## transfixer (Jan 30, 2019)

_The problem occurred before any work though. The brakes had worked fine for years before. I guess installing something wrong could show up even after years of working properly. I did read about people installing the longer or shorter shoes wrong._


Normally when one locks up after the vehicle has been sitting for an extended period of time its just rust that has developed between the shoe and the drum,  if that was the case here then they need to either get the drums turned, or back off on the shoe adjustment, to see if that solves the problem.  

   The equalizer/splitter/t-block only comes into play if the brake pedal was pushed before the wheels locked up. I'm not sure about one on a vehicle that old,  but most since the 70's or 80's have a valve inside them, that is supposed to balance fluid distribution,  that one being a 57 it might not have that,   

    I also have seen rubber brake lines that deteriorate on the inside and keep fluid from exhausting back into the master cylinder,  pressure from the master cylinder will force fluid through the line, but if the line is collapsed on the inside it won't release,   but you mentioned they had replaced the rubber lines I believe ?


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## Artfuldodger (Jan 30, 2019)

transfixer said:


> _The problem occurred before any work though. The brakes had worked fine for years before. I guess installing something wrong could show up even after years of working properly. I did read about people installing the longer or shorter shoes wrong._
> 
> 
> Normally when one locks up after the vehicle has been sitting for an extended period of time its just rust that has developed between the shoe and the drum,  if that was the case here then they need to either get the drums turned, or back off on the shoe adjustment, to see if that solves the problem.
> ...



From what I've read on a car that old, the block is just a tee. A parts guy told him he could use a block tee off the shelf but it wouldn't be OEM for a brake system.

Yes he has changed the rubber lines. I had that problem with a 65 Dart that I had. It would pull left when stopping and then pull right when stopping. Replacing the hoses took care of that problem. Mine weren't collapsing but were expanding in the rubber lines instead of delivering the right pressure to the wheel cylinders.

I was reading that one of the springs on the pads was a return spring that forced the fluid back up the line and back to the master cylinder. I might have thought that was the problem until he told me it locked up just rolling the car a few feet.

I'll try and talk to him today about it some more. He may just want to go ahead and turn the drums. New ones look reasonable on the internet if he can't turn his again.


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## Artfuldodger (Jan 30, 2019)

The rest of the story! lol
My brother said the brake drum slid right off. They cleaned it all up and slid it right back on. Then they rolled the wheel on the jack and it locked up with a couple of turns. They bled the brake and it released the wheel.
My brother said he could apply the brake pedal and release it, return to the wheel in question, and turn it while jacked up. It would spin freely but slowly get progressively harder to turn until it would not turn at all. This after a couple of turns. He could then bleed the brake and the wheel would spin freely.

He repeated this same precedence a few more times and the same thing happened. The wheel would spin at first but slowly lock up.

So maybe the return spring but he said he had a time getting the springs back on. Like they were still good.

He is going to try and swap the drum next to eliminate the drum being out of round.

Still though if he can bleed that brake, why does it release? Why can't the pressure return through the block and to the master cylinder?
He said he'd have to pull the header to pull the brake line block. If just a tee, the fluid doesn't have any trouble going to wheel.

I'm going to have to double check if that block is in fact just a tee.


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## Artfuldodger (Jan 30, 2019)

But, if he could apply and release the brake? Return to the wheel on the jack and spin it freely? It wasn't actually locked by the brake pressure.

Then when he would manually spin the wheel on the jack, it would progressively get tighter until he couldn't even turn it by hand. Weird.


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## Eudora (Feb 3, 2019)

I'm thinking it is a bearing/race issue? Or spindle?


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## Artfuldodger (Feb 8, 2019)

Eudora said:


> I'm thinking it is a bearing/race issue? Or spindle?



I was leaning that way myself. My brother just called and said it was the drum. He swapped it with the drum from the other side and the problem followed the faulty drum.

That being said he took it to the local NAPA store and it didn't mike out of round. It was too thin to turn though. My brother said it physicially looked OK. 
Might have been something else going on with the faulty drum. Lug holes maybe.


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## Crakajak (Feb 8, 2019)

Artfuldodger said:


> I was leaning that way myself. My brother just called and said it was the drum. He swapped it with the drum from the other side and the problem followed the faulty drum.
> 
> That being said he took it to the local NAPA store and it didn't mike out of round. It was too thin to turn though. My brother said it physicially looked OK.
> Might have been something else going on with the faulty drum. Lug holes maybe.


I have seen where the brake drum was incorrect( 1/4" width difference) and the brake pad was scrubbing the inner wall had to look at the brake scrub line close to find it. It was on a 73 jeep.


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## Davans (Feb 21, 2019)

You’ve got a Hub/bearing/race issue.


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