The Stovebolt Site Forums The Parking Lot Tons 'o Fun Wheel Cylinder Rusted Shut

I am in the process of replacing the brake systems on my 1948 1 Ton. I was able to find new wheel cylinders online but I would like to take current ones apart, hone them, and replace the seals, etc. My one problem is that the caps are sealed on from rust. My first thought was to soak them in PB Blaster for a couple days and see what happens. Wondering if anyone had luck with another method, or if soaking is my best option?

I will generally soak them in my parts cleaner or kerosene and have also used PB Blaster and still usually end up pounding them out.

Clean, hone, and clean cylinder walls with alcohol before appling fluid to insert seals.

I was trying to stay away from pounding, but its better than the alternative. Do you just put the casting in a vice and use a rubber mallet?

Buy the new ones. the ones i bought from napa were only $35 each and i didn't have to do the extra work to end up with a leaky cyl. my opinion. if you do the rebuild, check and double check for a rust pit. my2cents

daren

I would suggest soaking them in EvapoRust. You can't really pound on them because those little teeth are fragile. After you get the caps off I would only apply force to the outside of the pistons. It is really easy to fracture the middle of those pistons. Oh, I would not squeeze them in a vice.

Thanks for the input. I was finally able to get them apart with some PB Blaster and a little finess with a brass punch and hammer. Didn't have to use a vice to compress, just a support to knock the bottoms out.

What is the general technique for cleaning the rust off the wheel cylinders? I have a blaster and was thinking walnut shells, but wanted to know what worked for anyone else.

If they are that rusty, they may be too pitted to build without sleeving them.

New ones would be the way to go.

Two things you want to be able to do in these old trucks for certain. STOP...... and STEER.

Not worth it sometimes to chance old parts when new ones are out there fairly reasonable.

I was able to get the inside of the cylinders clean with some alcohol and I did not see any pitting on the inner diameter. I just wanted to get the rust off the exterior so I do not have this problem again.

As for replacing them, the front cylinders are not that bad but the rear ones are listed at $116 a piece. I budgeted for the replacement cost, but if I could stay away from it I would like to.

If they aren't pitted then they should be fine to rebuild.

Roy,

The best way to remove rust is with a lye bath and a little electrolysis. If you have a plastic tub, a battery charger, a bottle of lye and a piece of scrap stainless, you are ready to go.

mix up a solution of lye to water at the rate of one tablespoon to a gallon. NOTE, you can also use washing soda if the lye bothers you,

Hook the positive terminal to a piece of scrap stainless, hook the negative terminal to the part and put them in the plastic tub with the solution.

Turn on the juice. This will convert all the rust back to iron, but of course it won't fill pits or make rust solid. Basically it does the same thing as phosphoric acid, but better.

You will be amazed at how well this works.

Here is a neat link:

FIT's electrolysis bath

Kurt

i must have had really good luck, i have only broke 1. i let them soak for a while and drive them out with a brass punch on a wood block.

Will the electrolysis leave any material/residue on the inner diameter of the cylinder? I don't want to adhere anything to the inner walls and end up with an uneven surface before honing (they are smooth now).

I have never had it leave a residue other than a slight film where the rust has converted. You will want to immediately wash the part in water after you take it out of the bath and then dry it with compressed air. Wire brushing the outside as you clean it would be helpful.

You might want to try it first on something else if you are concerned about it.

The critical thing is to get the polarity right, because if you get it backwards, it will remove material.

Be sure to wear heavy duty rubber gloves if you are using lye. That slippery feeling if you get any of the lye solution on your fingers is the skin cells sliding off.

Be sure to read FIT's article.

Kurt

I read through the FIT article, and it looks promising. I have some fine grade walnut shells that I might try. If that doesn't work I might try the electrolysis on the wheel cylinders. I will definitely give it a try on the other parts that are caked in rust.