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My 1942 Chevy 1 1/2 has a very pitted master cylinder. I checked with a local brake shop and they said it could be re-sleeved for around $40. Has anyone had this done with success? It looks almost too close to the threads to be bored and re-sleeved. Cheap alternatives?

I have had some pretty bad ones that I honed with an Ammco hone. It works like a cylinder hone and I use a mixture of cooking oil and biodiesel for honing oil. After I get all the pits out, I polish it with a dingle berry hone. They wind up a couple of thou bigger than new, but the rubber cups seem to be forgiving. However they will not forgive any pits.

Even though I could have bought a new one, I had my master cyl. sleeved with stainless steel. I also had a couple of the wheel cyls. sleeved also. I figured that in the long run I would have brakes cyls. that wouldn't wear out. I run silicone break fluid,(don't use silicone if you have a vac-brake booster). I also replaced all the rubber brake connect lines. I have also honed cyls. till they were "clean" and just put new rubbers in, not measuring the size...they still work, don't leak.

I've honed out cylinders before like crenwelge suggests. Many of the worst pits seem to be in the center where the cup seals don't ride, so if you are careful and pay attention it works pretty good. When I do mine I try to stay within 5-7 thou. I think you can go to 10 thou safely, but I try to keep it down to a minumum.

Resleeving is a good idea though.

Do you remember where you had them sleeved and the approximate cost? Thanks, Kenny

kwhit -- $40 *is* cheap! For a SS sleeve job? Man, I'd break my own arming whipping out the checkbook on that one! I hesitate to go against Crenwelge's advice on trying the honing, but not all of us have his years of experience, skill and knowledge. From my limited years and skill, my opinion is this -- Don't go cheap on your brakes. One of our young Stovebolters wanted to go that route and very nearly lost his life (he's now a quadriplegic and his truck is on it's way to China as a coffee table-sized chunk of scrap steel). There are places to cut corners in this hobby, but brakes most certainly aren't one of them! If you have pits (and by your own admission you have pits), you need to resleeve or get a new/reman master cylinder. Period. There is no alternative. Some of the better NAPAs or the parts sellers can find the new or remanufactured brake parts for you. Don't even frig with the wheel cylinders -- just pull 'em out, throw 'em away and put new ones in. If your master cyl is pitted you can bet dollars to donuts your wheel cylinders are, too. Don't screw around.

Regards,
John

I'll second what John said!

But hang onto those old cylinders (don't throw them away) even if you do get new ones. The day will come when you can't get new ones and you'll be happy to have old ones to stainless steel sleeve. (or better yet sleeve them now)

Grigg

Good advice guys, Thanks...

New cylinders are still available for my truck but I am going to sleeve my parts instead. I am about to send off my master, slave and brake cylinders to be sleeved with tempered brass rather than stainless. The brass is much harder than cast aluminum and not much softer than cast iron. The hardness of stainless isn't necessary in brake systems and installation of stainless sleeves has much higher risk of breaking the castings. After removing and seeing what time and low usage does to OEM brake systems brass sleeves and quality VAT paint coatings should be the last brake components job this truck sees.

No matter what you do about fixing your brakes, check your brake fluid regularly. Most horror stories could have ended differently if a few squirts of brake fluid had been added.

I got new cylinders for my 48, I got the rears from The Filling Station and the fronts from Jim Carter. The one's for the rear wear American made and just like the originals, the one's for the front were from Argentina and not top quality. The keeper for the adjuster popped off and I had to reset it.

If I may still send off my front cylinders to sleeving.

Amen to checking fluid.
I do a "topside bleed" on all of my vehicles each yr, then a full bleed every 2 or 3 yrs. What I call a topside bleed is nothing more than sucking the fluid out of the M/C reservoir and replacing it with new fresh DOT 3 or DOT 4. I use a $1 turkey baster from the house. My wife gets a new baster every Christmas.
Cheapest preventative brake maintenance there is. Remember, brake fluid is hydroscopic (absorbs water). So if you don't get that old waterbound fluid up and out ever now and then, you get corrosion and pitting.
Watch out!, that fluid, if dripped on paint will eat the paint.

Check your daily drivers and that of your spouse. I assure you if you have not done this, the fluid will be the color of coffee! That is really corrosive!!! It costs you what? a little more than a cup of coffee per truck/car to prevent this corrosion. And you can do this task faster than you can drink your cup of coffee.

-Rick M.

If my feeble mind is working at it's peak performance.... that means a top side bleed you don't get air in the system.. right? As long as you don't touch the brake pedal that is.
(I am still a very green newbie when it comes to these matters)

YES, and the old nasty fluid has a habit of rising to the top..
after a week skim off the top layer.

Great tips guys, The type of thing you should think of yourself but never do!

reading this post makes me want to try my own sleaving. has anyone done this? i have thought it would be pretty easy to make a holding fixture for the wheel cyls or master using the mounting holes for use in my mill. what size wall stainless tubing is used? does it need to be finished reamed or is it good as is? do you hsvr to worry about fluid getting behind the stainless? do you have to have to cut a new seat for the valve to bottom out? well as i type this i guess i remember why i haven't done it yet.

I had my master cylinder resleeved with brass 10 years ago, this spring did a full brake job and the master looked as good as the day I put it in.

Next time I do a full brake rebuild it's all gonna be sleeved. Tired of dealing with cast parts, esp. when you look at the shoddy QC on todays replacement parts. My "new" master wont last nearly as long as my NOS '59 Hydrovac just due to the lousy metal in the new part. I'm glad the companies that make them can save money and charge less for thier parts, but what's the pont if I gotta replace the durned things twice as often???

I've never sleved any at home but I have bored wheel cylinders out on the mill to clean them up and turned new pistons to fit the bore. I did all wheel cylinders on my 46 with great sucess

Where do you get the brake parts resleeved?

I just had my system evacuated (1hr labor) and 3 qts of dot5 put in. My mechanic (for things like this I don't do) calls it the forever fluid as it isn't supposed to take on water....also it is blue...like them fancy terlet waters!

Total cost about $140, or about 45 worth of fluid if you do it yourself.

If you use DOT5 silicone fluid, make sure that the rubber components are compatible. Older rubber parts are made of a different rubber compound that reacts poorly with DOT5, it actually softens it, and in some cases, dissolves it. I know about that from personal experience.
I also would not call it "forever fluid". While it does not absorb moisture like the glycol based DOT3,4, and 5.1, it also doesn't disburse it in the system, either. condenced moisture in a system with DOT5 has a tendacy to pool in the lowest points of the system, as it doesn't mix with the fluid and DOT5 is lighter than water. Annual flushing is still suggested.

Anyone out there ever do any boring of master and wheel cylinders on a lathe? Any tips? I got a vintage craftsman/Atlas lathe for Christmas. Instead of my intial plan to send parts off for sleeving I'm interested in spending those funds figuring out a lathe setup and doing it myself as one of my winter projects. Also what are some sources to buy brass sleeve material and brass bar to cut new piston cups?
Conway68

I haven't bored an actual wheel cylinder.. but I've bored countless similar jobs in the lathe.

I'd start with a 4 jaw for ease of centering.
Use a dial indicator with a finger attachment to reach inside and indicate both ends true, use a brass or rawhide hammer to help true the outside end.
Then bore it to suit. Checking diameter with a telescope gage and outside micrometer, or inside micrometer if you have one.
Press the stainless steel sleeve in place, use green locktite shaft retaining (press fit) compound. Then bore or hone if necessary.

Don't forget to drill the ports for bleeding and filling.

Check www.McMcaster.com for seamless stainless steel tubing.

I've heard plenty of difficulties with brass sleeved brake components, never heard of a problem with stainless steel sleeved ones. Stainless is harder and therefore less likely to wear and is even more corrosion resistant than brass.
While you're at it might as well do the best job you can.

Grigg

Conway, you say you just got a lathe. Have you used one before? If you are not familiar with a lathe, I don't think what you are attempting is an entry level job. If you have experience on a lathe but just never owned one, have at it.

Grigg-

I was thinking tempered brass instead of stainless on the basis of some various web reading which suggested the tempered brass was preferred over stainless in brake and master cylinders as its still quite strong but more "forgiving" and has less risk of breaking the castings. What type of problems have you heard of going with brass?

Conway68

Crenwelge-

I've used a lathe years ago at a novice level, never as my employment. I certainly cannot claim to be a skilled machinist. I actually thought this would be interesting and doable with some practice on doing some pipe boring or even on some other scrap car wheel cylinders before actually touching my C60 parts. I don't know how else to improve my skills other than read all I can, ask questions, and give it a try. Actual machinist training for the part-timer seems to be a thing of the past and becoming lost skills. Recommedations greatly appreciated.
Conway68

It seems that you are beyond the point of thinking you can do things because it looks simple. If you realize that you have to practice on some junk, you should be just fine. I'm sure you are to the point that you can measure and take small cuts and measure again.

What I know of brass sleeved wheel cylinders comes from three guys I worked with (at an antique auto restoration shop) that had previously worked at a different shop that also brass sleeved wheel and master cylinders.
They commented that a fair number of them came back for rework.
And most importantly they had a few occasions when using the brass sleeved cylinders on vehicles they were working on in the shop... seems occasionally the cups stick to the cylinders then when you step on the brake nothing happens. Ended up with one car run into a wall when the brakes didn't work. Only explanation they could come up with is the brass was the problem, as it never happened with cast iron. (and I've never heard of it with stainless)

At the shop I (and the three guys) worked at we used stainless steel sleeved cylinders and not once did we have a problem with them.

As far as splitting wheel cylinders when installing sleeves, a proper fit will avoid that, yes it will take a tad more patience and or skill.

So obviously take my advice on the brass with some skepticism, it's second hand for me, and 3rd hand for you...
But from my experience with stainless ones and using some logic I see no reason to use brass over stainless.

Grigg

wow, did all 8 cups stick at once? it seems like a worse case would be one sticking and the truck just pulling to one side but hiting a wall! wow. reading the post def get me excited about trying it. i like machining brass a lot better than stainless but i like the suggestion of why not do it best.
does anyone know what thickness of wall tubing to use? there is a place in town here that sells brass rod in all dif diams, and turning rod is a snap- i don't usuall mess that up. i usually have 1/2 and 3/4 trucks so the bores are usually around 1 1/8" i think. just wondering how much of the cyl you would have to remove. i still like the idea of doing it on a mill. i would hate to chuck a master cyl in my lathe. i do have a tip though.... don't leave your key in the chuck.

No definitely don't think it is simple or lacking the recognition of risks with botched brake parts. Small parts and small lathe (6" x 18") has me thinking its a reasonable project to take on to build some skill. I also know of some freinds of freinds that are career free hand machinists I also thought I'd see if I could push some $ at to come over and look/help with appropriate setup. The wheel cylinders (7/8" front, 1 1/5" rear) I think would work great with a full chuck to tail stock line bore setup with standard over the counter tool holding options. The double barrel master (1 1/8" clutch side, 1 1/2" brake side)concerns me more as hoggyrubber mentioned as I don't have any good concept yet of how to best attack that setup. Might still send that out versus trying to rig a good tool hold for it. I also still need to find out what the appropriate wall thickness should be. The master would need to be thicker than the wheel cylinders to accomodate cutting the grooves for the snap rings.

Great info Grigg-

I was actually under the impression brass was the better of the two against corrosion as the benefit for going that route in addition to not needing the superior hardness of stainless in brake systems. One sleeving shop emphasized use of only tempered brass and was a hedge against breaking castings of impossible to find vintage corvette and other obsolete parts. I wonder if some of the brass problems were with the use of non-tempered softer brass.

Conway68