VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 1937 chevy front hub removal

brake cylinder froze up and I can't get hub off to free them up or replace because I can't adjust them down.

That is always a problem. You could try to back off the adjuster after spraying some penetrating oil into the adjusting hole first.
I assume you know the adjusting hole is behind the tin cover held on by one screw on the side of the drum.

You don't say what you mean by can't adjust them down. Do you mean that you know where the adjustment is and they won't adjust or are you not seeing how to access the adjuster? Gene points out the adjuster is accessed through a small hole in the front of the brake drum that is covered by a stamped steel cover that swivels on a screw to cover/uncover the hole.

I know where the adjustment one half inch hole is, I'm saying I can stick my brake adjustment tool through the hole to the brake cylinder toothed adjustment ring and it will not turn, its froze/rusted up. So I can't adjust the brake shoes down far enough to pull the brake drum over them to get it off.

That clarifies it. Thank you.

Does the drum rotate easily to align the adjuster hole or is it dragging?

Mike

Rotates easily, slight drag on one side of shoe.

If it was me I'd try using a small hammer and a flat blade screwdriver, put the blade of the screwdriver against one of the lobes on the adjuster cup and use the hammer to try to drive it in a counter clockwise direction. You may end up destroying the adjuster cup but if you're going to replace/rebuild the cylinder anyway it's not going to hurt. Driving it in that direction may give you more directional force than prying it.

Take a good look at a picture of the adjuster cap. You will see 2 circles of “teeth”.

The smaller diameter set is the one you are supposed to use to turn the adjuster.

The teeth on the larger diameter ring run underneath a flat spring on top the cylinder. That is what locks the adjuster in position.

You should be able to rotate the brake drum so the hole allows you to turn the larger teeth. That has more leverage on the adjuster so you might get it loose.

The other issue is that you don’t know where the adjuster is frozen. Is it stuck on the wheel cylinder body? Or are the threads on the adjuster frozen? That is the most likely scenario.

I agree with Tiny. Spray your rust penetrant liberally. Then use an old screwdriver with a fairly blunt blade tip to try and move the adjuster. Hit it pretty good with a hammer to try and knock things loose.

Plan to replace the cylinders. I made the mistake of trying to salvage the originals on my ‘37. 2 years later they were all leaking. The bore was too far gone. Plus about the only way to get new adjusters these days is buy a new cylinder.

Thanks gentleman, good advice about the hammer and screw driver, I will try that. Won't the penetrant soak into the brake lining and cause them to slip? I did try that but was very conservative with it. I was planning on honing the cylinders, with a rebuild kit but I guess that's old school now days. I can't tell where it is frozen, the threads on the adjuster ring, or the screw adjuster it self. Any way I can't get back to this this weekend to much other stuff going on, Christmas you know! THANKS

My limited experience with soaked brake shoes is they can be washed with lacquer thinner (what I've used) which leaves no residue or aerosol brake cleaner which also leaves no residue then allow to dry. You will likely experience some grabbing when you step on the brakes for a while but that goes away fairly quickly in my experience. If not there are brake shoes readily available. Also you can have the cylinders sleeved by a machine shop if the old cylinders are too far gone and new cylinders aren't available.

Cleaning brke linings with solvents is not always the best move. The solvents help the fluuid or grease to soak farther into the lining material.
If the aluinum piston is rusted into the cylinder bore the cylinde willl be pitted and not rebuildable not to mention the condition of the aluminum poston.
All the commo brake parts are readily available and at fairly reasonable prices....I would recommend replacing all the hoses and wheel cylinders sooner rather than later.

Removing the two little bolts that fasten the cylinder to the backing plate may help in the drum removal.

I forgot about the loosen the cylinder mounting bolts trick. I sure would give that a try.

Gene’s description of the cylinder condition is exactly what I encountered. The aluminum pistons had bonded in the cylinder. When I knocked them out of the cylinder there was heavy pitting in the bore where material was torn away as well as rust. Despite a lot of honing the pits never went away completely. Because they were near the middle of the bore I thought it could get away with re-using them by installing new pistons and seals. At that time you could still buy rebuild kits that included pistons. I have not seen those for at least 5 years.

If it rotates easily I would bolt the tire back on and this will give you more leverage to twist a pull and it will probably get it off.

So nobody has mentioned that there are two adjusters. If the outer bearing is removed from the hub there should be lots of wiggle room to encourage things to move. If the bearing is still in place, I would remove it.

I agree, remove the outer bearing so you can wiggle the hub and drum back and forth and there are 2 adjusters, one on each end of the wheel cylinder.

Once upon a time, years ago, I had the same problem on my '40. As old216 suggests, I removed the outer bearing, cocked the hub enough to get a large screwdriver between the brake drum and the brake backing plate and started prying. Using the first screwdriver to hold the drum out, I used a second screwdriver to work around and slowly pry the drum out over the shoe. My shoes had worn into the drum enough to leave a slight edge on the inner drum. I was able to pry hard enough on the brake adjusting teeth to break them off the adjusting cap. Between the galvanized adjusting cap, steel adjusting screw, aluminum plug and cast iron wheel cylinder I think some strange electrolytic corrosion happens because I had to do the same thing to back wheel years ago. Gene's idea of taking the bolts out of the wheel cylinder may give you a little more wiggle room. Once I had the drum over the edge of the shoe, it was fairly easy to pry off.

Originally the aluminum piston had like an anodized coating on it to prevent corrosion. Once that is removed the piston will stick very easily. Years back the pistons came with new pistons but not any more. New wheel cylinders are the best bet if you plan on keeping the car for more than two years.
On my '39 I packed silicone grease behind the adjusing cover to prevent moist air from entering aroud the piston to wheelcylinder area.

With the later Bendix brake there is a solid rubber boot at each endof the wheel cylinder which works better in keeping moisture out - but the pistns can still stick but not as often.

Silicone brake fluidalso helps as it does not attrack moister like glyco brkefluid does....but to used it you have to replace all rubber parts in the brake system first.

Thanks for all the good information guys, I haven't gotten back to this problem as yet, but I will keep to informed to the result of the issue when I get back to it soon.

I have gotten them off when the shoes were tight just by wiggling them back and forth and prying against the backing plate. Good luck!!!

I know exactly what you are dealing with. Recently purchased a 38 Master, pulled to one side when braking so went to adjust the brakes. Not a chance. Was able to "pry" the drums off the front using the big screw driver and prybar method (figured if I broke something too bad, the brakes needed work anyway). The adjusters were seized bad, wire brush, oil and a channel lock working back and forth for hours finally got them to move. After putting it back together they were still to "stiff" to adjust through the holes so ordering new for the Spring. Good luck. Should be a fast easy job but not for me.

Had this problem removing a drum on a truck project some years ago. After trying many, if not all, of the previously offered helpful options to avail, a slightly modified three jaw gear puller was used. Finally had success and without damaging the drum.