The Stovebolt Site Forums The Shop Area General Truck Talk Talk to me bout Wheel Cylinders!

Lets Talk Wheel Cylinders
First of all I’m working on a 3/4 ton Chevy with 12”x 2” Huck rear brakes with 1 3/8” wheel cylinders. Second of all I’m a bull headed old cus that would rather rebuild something rather than throw-it-away. I think it has something to do with the generation I’m from! Many, many years ago, in another place and time, I worked in the automobile trade as a counter man and machinist, with Chevrolet and in independently owned aftermarket stores. If I remember correctly, I think the line of brake parts we carried were EIC. They supplied kits and individual brake parts in handy boxes, for rebuilding all parts of the brakes such as Bendix adjusters, dust covers, springs, bleeders, pistons, and CUPS! I find that most of the vendors offer most of the parts, except for the CUPS.

I’ve looked on the internet and I have searched all the CarQuest, AutoZone, Napa, etc., stores in my local area and can’t find CUPS. Does any one know of a source for wheel cylinder CUPS? I don’t want to spend fifteen or twenty bucks on a kit, just to get the little rubber cups that are manufactured by the billions and should sell for 10cents each, but are probably two bucks now.

Thirdly I want to know just how far the cylinder can be safely honed before the standard cup won’t hold pressure. I have been unable to find any literature that addresses this subject. If I could find a site for the manufacturer of the cups or wheel cylinders, I might be able to get an answer to this question. But alas, they are as elusive as the cups are.

I may have to, and I have no problem with, boring the cylinders out to the next size which would be 1 1/2”. I can do that in either the lathe or a Bridgeport mill. There is plenty of meat in the casting so that would not be a problem. In the later case I could finish hone the cylinder to 1.500” exactly so the question of a seal for the standard 1 1/2” cup is a non issue. Besides, the casting numbers on the 3/4 ton and the 1 ton wheel cylinders are the same, the bore is the only difference.
Now I know there are those of you out there that are saying, WHY would you want to go through all of that, when you can buy a new wheel cylinder for $50??? Simply, because I’m retired and I can, that is if I can find the cups!
Appreciate any feed back, even if its negative.

Denny Graham
Sandwich, IL

Denny,try White Post Restorations in White Post Va.
On the web @ www.whitepost.com They sleeved my wheel cylinders at a low cost.They just might sell you the cups you need.

Denny,
I've tried to buy just the cups before and was unsuccessful. Also I've read that the anodized
original alum. pistons can corrode quickly when re-used because most of the anodizing is gone from the surface, especially after you clean them up. Maybe you could bore the cylinders and re-sleeve. Here is an article on Huck brakes.

Denny,

I looked at this rebuilding verses buying new thing on the wheel/brake parts. I decided that since I could buy new one, I would risk the rebuilding and having one fail shortly after. On our truck(2 Ton) its a lot of work to pull the wheels, hubs and drums to fix a bad cylinder. A pickup should be a little easy, but who wants to go back and redo stuff. I will say that we bought a new Wagner master, and it failed with a few months, but they replaced it free. Its kind of a crap shoot on whether or not to replace or rebuild most of the stuff on the trucks. Since I can get all the parts new from Wagner, I think its better to go with factory spec stuff, even though I have the tech to rebuild them.

If you have the time to wait, check out ebay. Or you can get sets for reasonable at swap meets. I had the 1 1/2" in my coe. I spent 15$ on each set just for the same darn reason. Why buy new when the old one works fine! Im impatient though, so if I can get it at the FLAPS, Ill just pay a little extra.

Jeff

I just rebuilt the rear cylinders on my '63 c20, 1 1/8" Bore. My Chevy shop manual listed .002-.004" between piston and c.wall. Don't know if older shop manuals list too. I never done drums before, I think I may have over honed 1 cylinder, I will find out. I am not retired, but I am poor and if I can try to rebuild for
$3 /wheel vs. $50-60, I'm gonna try to rebuild. Besides it way way fun too, I get to see how it all works in there. My rebuild kit didn't include 2 metal discs that were attatched to each end of spring on original w.cyl. I had to clean and reuse these things, they were filthy, I wish my rebuild kit included them with the springs, cups, and dust covers. I hope you can find just the cups Denny

I love your attitude. I,m from the old school. We used to rebuild a lot of stuff ourselves. I used to stock all the popular sizes of wheel cyl cups. Now the stores don,t even stock wheel cyl kits. Some of the brakes now they wan,t to sell you the whole backing with cyl,s &shoes & attaching parts. I think the cups are still available but you would have to buy a box of 10.
I still do my own starters & Alternators.

Last time I did my front wheel cylinders on my '50 half ton the cups came with the kit, maybe 4 years ago from Chevy Duty. I remember them being Wagner kits. They have held up just fine, I never bothered to check the bore.

It was such a hassle that I'm probably going to go to disc brakes. My drums are about done and they are about impossible to find.

I really wanted to rebuild mine as I find that much more satisfying. Unfortunately they were badly pitted and so I had them sleeved with stainless and rebuilt. My 51 1 Ton has 1 3/8" bores.

I have straight honed wheel cylinders before. I don't completely recommend it though. It has to be a "fixed" staight hone though (like a sunnen). I would shoot for .005" to .007" max. to clean them up. As long as there are not pits where the cups ride you will be OK. If there are pits in the center where the spring is, and th ecups don't ride , that won't effect anything. If you can find replacements for $25 or less, I wouldn't bother trying to hone them. Be careful and know what you are doing when trying to hone them. Bad brakes will cost you much more than new ones.

Denny, if you've got access to a Bridgeport or a lathe with a 4-jaw chuck, there's no reason you couldn't bore the cylinder a little oversize, press in a stainless steel sleeve, and bore/hone back to original size. The cylinder will be better than new, and it will never rust-pit again. Of course, the brake line and bleeder holes will have to be redrilled, but that shouldn't be a problem. Use a Sunnen connecting rod hone for final bore sizing and finishing. I suppose you could also build up worn wheel cylinder pistons with hard chrome, and centerless-grind them back to original clearance. You'll have $200.00 worth of labor time in a $30.00 part, but if you don't count your labor, have at it. Dorman products used to supply our bulk wheel cylinder cups back in the 50's and 60's, but I believe that company has been bought out by another outfit some time ago. Try Hemming's Motor News for new-old-stock brake parts ads. Somebody's probably got some stashed away and they'd love to get rid of them.
Jerry

Denny, the only way I found/find just the cups is to go to the oldest parts houses you know are still around. I got lucky and found them at two different "old" places but now they are out of them. I am like you, I don't like spending the money for the entire kit when all we need it the CUPS. I've rebuilt many, many cylinders using just the cups and never had a problem. I even use the hand drill hone's but try to keep it moving smoothly. If you think about it the cups do not actually move more than the width of stones on most hand held hones and if you keep it moving consistently there will be no problem. I worked at the Chev dealership in 1965 and don't ever remember ever having any problems. God luck what ever you decide. And your right, its nice to "do it yourself".

George, taint got into the starter and generator yet, all is well there so far, but that day will come I’m sure. Dad taught me how to turn a commutator and I still have his old growler in the shop. Bearings and bushings are a shoe in and as long as the windings all check out good we’re home free. Oh, and a box of 10 would be fine, or I would even take a dozen or two so when the next one comes along I won’t have to go through this exercise.
Fred, as I said, mine are 1 3/8” also on the 3604. I ordered 1.370” +/- .004” x 1/16” wall brass tubing from McMaster last night and have drawn up a fixture and scrounged up the material to position the cylinders in the Bridgeport mill for boring and drilling. I’ll face of the sleeves on the lathe, press them in and hone them to 1.3750” so that solves the question of “how much over size you can go”. Now the only problem is finding cups.
A Sunnen hone is not necessary to hone a wheel cylinder a few thousands of an inch. I’ve honed many in past years with wheel cylinder hone in a drill and never had a problem. I keep the hone and cylinder in a kerosene bath and keep it moving. Now if you have to hog out a bunch like .015”or .020”your probably gonna get some taper, but then again you’re probably gonna be standing there for an hour to do it, and go through a couple of sets of stones. If ya gotta take that much out to clean it up you should replace/re-sleeve it. People often misuse a hone as a boring tool, it is a finishing tool and should only be used to clean up or final finish a surface. If you have deep pitting, as I do in these Huck cylinders, then honing just taint gonna do the job. I’m already .005” over on the bore and still have some pitting, that’s why I’m gonna re-sleeve them.
I’ve been reading a lot at the rebuilders sites on re-sleeving wheel cylinders and the brass is the just as compatible as the SS, and much easier to work with.
The pistons in the Huck cylinders are not rocket science as they say, they’re simply an Aluminum plug with one side bored out, an after supper project. I do agree that corrosion does need to be addressed and I have anodized small Aluminum parts before using a storage battery and sulfuric acid bath so that’s not a problem either. You can even stain them Red if you want to!!! So out of the lathe and into the bath for the new pistons.
Hard chrome and centerless grinding? Naw, the pistons that were in there look like they were cast right to size, no machine marks on any of the 4 sets I took out. I found the clearance specification to be .002” to .004”, no need to grind that. The pistons in the Huck brakes run dry in the cylinders and there is no rubber dust/water seal so it is no wonder there are problems with them after 50+ years. From what I can figure, if you run a truck with them through a puddle that’s up to the axles your gonna get water in the outer bore of the cylinder, that would account for the rust and oxidation that had the pistons seized up in all 4 cylinders. I had to drive the pistons out with a wood punch. And can you believe it, people were driving this truck in city traffic when I bought it! I honestly don’t know how it was stopping because I found not one cylinder that was working and all of the pivot points on the brake shoe links were froze up also, had to drive them all out with a brass hammer.
Now if I can only find those 1 3/8” cups
Denny Graham

Availability of cups must depend on the local store. The NAPA store (not that old) in my town has a complete selection of brake cylinder cups. I just tell them what size I want.

Denny

I rebuilt a complete set of hucks on a 47 1.5 ton for about $9 including brake juice. The rubber cups were purchased at Bumper To Bumper for $.50 each. One thing you need to look at is the master cylinder and make sure it has a good pressure retainer, it should keep about 1 to 2 pounds of pressure at rest. Even a new tight wheel cylinder will seep without a slight amount of pressure at rest.

Don, I just called all the NAPA, CarQuest and semi indipendant stores in my area today. One of them has some cups but only up to 1 3/16", the rest came up empty.
I found a source for several rebuilds on the VCCA truck forum so problem solved till next time!
Who is Bumper to Bumper Todd? Must be local, never heard of them here in the Chicago area. I did a complete rebuild of the master cylinder last month, the PO had "rebuilt" it, that's why the day I bought it I only made it 10 miles before the brakes completly locked up and had to have it towed home the last 20 miles. All he did was take it apart and a new kit in it, I don't think he even cleaned off the mud. Then he had the push rod stop in backwards keepin the compensation port blocked, that's why it locked up.
Denny Graham
Sandwich, IL

The cups I bought were Wagner parts so any parts store should be able to get them, 1 1/4 front 1 3/8 rear. A question for you Denny how do you adoize the aluminum pistons. I have bored and honed huck cylinders before and made my own pistons with good results. I bored the cylinders with a boring head and a home made angle plate and a finish hone. Worked on them for two weekends but only spent $9, guess I put some 9 year old in China out of a job.

See if I can find the strength of the bath, it's been a few years since I did it last. I just used fresh sulfuric that we kept for filling batteries. If I remember correctly I diluted it. Connect one side of a battery to the part and one side to aluminum foil that surrounded the part and let it cook for a while. I pulled it out and checked the surface for continuity periodically with a multimeter. The oxide that forms on the surface is non conductive. When I’m at that point, I’ll dig through the files and refresh my memory. Right now I’m busy making fixtures, bearing removers, parts for the door regulators, new brake lines, hose adaptors that screw into the bleeders and a few dozen other projects.
And that’s the point I have been trying to make, all of the parts stores that I have contacted are not interested in getting cups for me. I found a bunch of NOS cups but I’m a little leery for fear that they would be dried out.
Denny Graham
Sandwich, IL