The Stovebolt Site Forums The Shop Area Engine Shop rear wheel cylinder rebuild

hey everyone, did a search, didnt come up w/ anything. can someone walk me through a wheel cylinder rebuild? I want ot buy the kit and try it. how do you get them apart, tips on getting everything back together. i have them off and soaking in penetrating oil.

Not alot to it, especially on the trucks with the Bendix style brakes. To disassemble, assuming that the cylinder was still funtioning, is simply a taks of taking off the boots, then carefully pushing the guts out. If it was seized, then things can get interesting, and IMHO it would be best to install new complete wheel cylinders. Next, would be a thurough cleaning, brake cleaner will be fine. Inspect the inside of the cylinder for gouges or pitting. Ideally, you will also want to check the fit of the pistons for wear, you will need a feeler gauge for that. If things look ok (no deep pits or gouging), then you will hone the cylinder with a brake hone. Use clean brake fluid as the lube for this-NO PETROLEUM BASD LUBES!! Once a nice surface has been achaivesd, and the cylinder is free of pits and such (again, if it's real bad, get new cylinders), thuroughly clean it again, check the fit of the pistons. To reassemble, the spring and cups go in first, lube them either with the lube provided in the kit, or if none was included, clean brake fluid. Then the pistons go in and the boots go on.

58stepside,

If the bore is good, no deep pits or rust holes, it's a real simple deal. Pull the pistons, boots and spring out of the casting and remove the bleeder screw too.

Buy a wheel cylinder hone and hone the bore using a small drill, some type of lube like diesel, cleaning solvent or even a spray lube like WD40. This just keeps the stones from filling up.

Use a in/out stroke with the hone, running from end to end to create a even pattern. Not much is needed, just enough to make it bright and remove any rust ridges.

If there are deep pockets you couldn't remove, it might be a no-go deal. Stick the small spring in and each piston, being sure to orient them in the 'lip-in' direction.

Stick the boots on, the bleeder screw in and it's a done deal.

You will want to wash the wheel cylinders in something to clean them up before reassembly and squirt some brake fluid into them as a lubricant when installing the two pistons.

It's an easy job, but new ones are cheap too (I think), and they would be guaranteed to be good and leak free! Give it a try, I'll make you feel proud.

Stuart

Pretty simple assembly. Remove the boots & pull out the pistons.
If they have enough recess in the back of the piston a pair of snap ring pliers works good to remove them. If they are really stuck you may have to drive them out. Remove the cups & spring. Make shure the bleeder screw will come out & clean it up. You will need a brake cyl. hone. Hone the bore of the cyl till it is smooth. If you have any pits left that are anywhere but in the center, you will need to buy a new cyl. unless its a rare model which you will send & have it sleeved. Lube the cyl. with a little silicone or brake fluid & put the spring, cups, pistons, && boots on.

Wow, lots of answers really fast!!! I love this site. I'll give it a try. Wrenchbender Ret. what do yuo suggest using to drive them out? maybe a socket? I am doing this on a 56 3/4 ton longbed. Was going ot go new, but its looking like $300 + for everything. thought if I could save a buck, I would.
I noticed I am missing one wheel cylinder connecting rod. looked everywhere cant find one. got suggestions??
Got a crazy one to tell you too, took off the bed, all that was left was the cross bars under the bed. started to use a bolt cutter to remove the cross bars and evidentally the shackle on one saide was broken and was being held in place by the cross bar, when I cut the bolt, the bar shot straight up, the back of the leaf springs came up above the frame by about 2 feet, the rear of the driveshaft hit the floor and the whole truck shifted foreward enoigh to be only on the front legs of the jackstands. scary stuff. so not the truck is to figure out how to jack up the frame enough to get close to the much higher rear of the leaf springs to put new shackes on.

That rod can be hard to find. Probably one of the fellow Stovebolters has one laying around the shop or yard. Post in parts wanted. Boy that is scary, that truck falling like that. Thats something all of us came up with the same info at the same time. They all type faster then I do.

If you wrap the wheel cylinder in a rag, you can apply compressed air sparingly and the pistons will pop out. If only one pops out, you now have access to tap the other out.

Stuart

Thanks everyone, I will give it a shot tomorrow