Brake drums ?

[acarlson]

One of my brake drums is very difficult to remove. The other 3 just slide right off. The 4th seems to be binding on the shoes. The drum turns freely - just removing it is a problem. I tried screwing the adjustment wheel a number of turns just to see if contracting the shoes would make a difference - it didn't.

Any thoughts on this one ?

Thanx -

Alec

[Jerry Whitt]

Probably the big hole in the center of the drum has rusted to the hub. Try some wd40. Let it sit for a while. Then some pry bar force. Finally after off, use a file or small grinder to enlarge the large hole a little


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[terribleted]

Or you need to loosten the adjuster more

[County98]

I had one that wouldn't cooperate as well. Soaked it in PB Blaster every day for a few days and then started banging from the back edge with a rubber mallet. Eventually it started to move...a little. turn, hit, rock back and forth, repeat about 50 times. Eventually it will pop off.

[b74eqcm]

If they haven't been off in a long time, there may be a wear lip on the drum. The brake shoes don't reach all the way to the edge of the drum, so sometimes the drum wears, but leaves an unworn 'lip' at the edge. If it wants to wobble, but not come off, this could be the problem. You just have to loosen the adjuster all the way to get it off.

If it's frozen (won't even wobble) then I do what Shayne said ^^

[acarlson]

I can get the drum off and put back on - it's just that getting it off is a struggle. I'm beginning to think it may be a problem with the hold down spring. I think whoever did the brake job the last time put the wrong spring on the right side shoe. I can easily pull the right shoe away from the backing plate compressing the spring. The left side is much stiffer. My current theory is that as I pull the drum off, the right shoe gets pulled along with the drum, rotating as it gets pulled till it binds. If I hit the drum with a rubber mallet you can hear the shoe release and snap back into place. Anyway, I'm going to get a new correct spring and see if it makes any difference. I'll let you know.

Alec

[66vairguy]

Yes there are different springs and the "nails" that through the backing plate are different lengths on frt. vs. rear. Not unusual to find the wrong nail length, wrong spring, or an incorrect spring cap that goes over the "nail" and is turned to lock. I don't have the sizes Corvair uses handy, but I bet Brad will post.

BTW - The usual brake spring tool to turn/remove spring cap off the "nail" doesn't fit well on the Corvair brakes. Most use a needle nose vise grip (don't over thighten) to install/remove the spring cap.

[64powerglide]

Be sure to check the wheel cylinders before installing new shoes.

[acarlson]

An update... I swapped the left and right side rear drums. The drum which was sticking when installed on the "good" axle still sticks. The good drum installed on the "sticking" axle slides on and off just fine. It appears that the problem is the drum not the shoes.

I have never liked the braking performance of my Corsa and given the trouble I've had I'm just going to replace and rebuild all the brakes.

Thanks to everyone for your comments.

Alec

[66vairguy]

An update... I swapped the left and right side rear drums. The drum which was sticking when installed on the "good" axle still sticks. The good drum installed on the "sticking" axle slides on and off just fine. It appears that the problem is the drum not the shoes.

I have never liked the braking performance of my Corsa and given the trouble I've had I'm just going to replace and rebuild all the brakes.

Thanks to everyone for your comments.

Alec

The Corvair LM brakes are relatively large for the weight of the car (same size as 65 Chevelle). High pedal pressure is a common complaint. Years ago a Corvair enthusiast in New Mexico discovered the issue was the newer brake shoe linings - the lining material was too hard. He found a shop that would install a "softer" lining and reported his brakes worked like they did when the car was new. I've run into the same problem and was lucky to find a place that does truck brakes and the owner does hobby car stuff. The shop used a "soft" lining on my shoes and arched the shoes to the newly turned drums (very important). After break-in the brakes work fine. Understand that manual brakes will always require more pedal pressure versus power brakes, but not an unreasonable amount.

If you are going racing - stock drum brakes are marginal and you need disc brakes.

[firstgencamarojunkie]

I have the same problem / when driving my '65 Corsa I have to be very careful as I don't trust the brakes to stop in a reasonable distance. I've rebuilt all four wheels, changed the cylinders, turned the drums, installed new shoes, and bled the entire system. The car stops but it seems it should do better. Was considering converting to discs but don't like the cost. I understand that we used to be able to get metallic linings and that those performed much better. I'd be interested to know where I can get the "softer" linings - or metallic linings - so I can feel a bit more confident driving the car - Andy.

[acarlson]

I read somewhere on the net that O'Reilly's auto parts brake shoes are a little softer then others. I bought a front and rear set today. I'll post a review once I'm back on the road.

Alec

[toytron]

Another thing to consider when you reassemble them is to put a little anti seize on the hub to help prevent the reformation of rust.

Ed Stevenson