1962 brake advice

[Philip P.]

Re: 1962 brake advice

Need to know, why even rebuild the wheel cylinders a complete kit from Corvette Central is under $250 for all four wheels. Are the replacements that bad?

[Elwyn S.]

Re: 1962 brake advice

Philip, I am not sure if it matters about the aftermarket replacement wheel cylinders, that is why I am asking the question. I do know that I cannot find wheel cylinders for the front with the correct bore of 1 3/16, everything I am seeing out there is 1 1/8. I do not know if this is a real issue. I drive the car alot when I can and I like keeping the car original, but within reason since it is a driver quality car, but mostly all original. Thank You for bringing the question up.

[Joe L.]

Re: 1962 brake advice

Joe, you are probably right. I have made the decision to look at the wheel cylinders, as Paul young said in the previous post it would suck to have the brake pedal go to the floor... again in my case. What about the steel lines being almost 50 years old, would you advise changing those also. My problem is I do not have a lift, all this work will be done on jack stands.

Elwyn-----

If you find serious corrosion in the wheel cylinders, I think you might be wise to "extrapolate" that the same condition exists in the steel lines. On a C2 or C3 replacing some of the lines is almost impossible with the body on the frame. However, I believe it's easier on a C1. I would replace with TBW (tinned bundy weld) stock-type lines. While I'm a big fan of stainless steel everything, I think TBW is best for brake and fuel lines. The TBW is going to last you far longer than you're ever going to need it and will be "immortal" if you use DOT 5 silicone fluid. Stainless lines can be a problem sealing at the flared joint.

By the way, brakes are important. You want them to be 100% right. This is especially important on a car with a single circuit brake system like all C1 Corvettes.

[John F.]

Re: 1962 brake advice

You can buy the 1 3/16" rebuild kits at Advance Auto. That is where I got mine. Save your pistons if they are decent. The kits do not include the pistons, just the spring, seals, outer boots.

[Philip P.]

Re: 1962 brake advice

I am sure I will be corrected, but it looks like the 1 3/16 are standard for 60-62 and the 1 1/8 were used on everything from about 1950 to 59 and then became the HD option in 60-62. I have no idea what the 1/16 inch will make in the function of the brake system or why it was changed. Anyway that is what it looks like in a interchange manual I have. I would rebuild if they can be done without sleeving. If not, I would replace them, but that is me.

[Jim L.]

Re: 1962 brake advice

Philip, I am not sure if it matters about the aftermarket replacement wheel cylinders, that is why I am asking the question. I do know that I cannot find wheel cylinders for the front with the correct bore of 1 3/16, everything I am seeing out there is 1 1/8. I do not know if this is a real issue.

Elwyn,

Although there is nothing wrong with brakes that use the smaller 1-1/8 wheel cylinders, the pedal effort is noticeably greater than what it would be with the 1-3/16 cylinders.

If your original, large wheel cylinders can't be rebuilt, you have two options: 1. Look for replacement large wheel cylinders. They show up on EBay from time to time. 2. Convert to replacement 1-3/16 wheel cylinders.

On my '60, I put up with the 1-1/8 replacements for several years but, a few years ago, I decided to re-install the large wheel cylinders. While I have the original, large wheel cylinders for my car, I decided to make the project "interesting" by tracking down a current-production, large wheel cylinder that could be adapted to our early Vettes.

I ended up purchasing a pair of front wheel cylinders for a 1969 International Harvester. These have the proper bore, but require a trivial modification to the backing plate to install. Once on the car, they look, fit, and function just like originals.

The backing plate modification involves grinding away a little bit of material from the piston safety stops. The original distance between the stops is as shown:


To fit the IH cylinders, which are slightly longer than originals, open this distance up to this:


That's it. You are done. The wheel cylinders are otherwise a bolt-on:



One caveat: I have heard from one other person who has made this change that there is some slight interference between the brake hose and the spindle support. I didn't experience this so I think it's more a function of the source of the hose than the presence of the IH cylinders. You might want to check this, though.

A final comment: I used DOT 5 fluid (and have for 30+ years) and didn't go to any unusual lengths to do so. I installed the cylinders, added fluid, bled brakes, went driving. That was 4 years ago. No problems.

Good luck,

Jim

[Philip P.]

Re: 1962 brake advice

Jim, What model International were these used on .
Thanks
Phil

[Elwyn S.]

Re: 1962 brake advice

Jim,
Thank you for your detailed response. I have seen these pictures and your work around on the wheel cylinders when I was doing research in the archives.
I pulled the front wheel cylinders last night and as expected by most that have responded to this post they did not look real good. I have decided to try and hone these out and rebuild if I can. If I have little success with honing I am going to send these out for resleaving along with the rear cylinders.
Did you replace your steel brake lines when you rebuilt your brakes? If so, how hard is to replace the line that goes under the engine? Also, I am looking at converting to dot 5 but I am being told if I do that Apple (where I will send the Cylinders to) will not warranty them. They say that D0T 5 causes the seals to swell and leak ??? Have you ever heard of this?
Thank You, Elwyn

[Jim L.]

Re: 1962 brake advice

Jim, What model International were these used on .
Thanks
Phil

They are available from NAPA as part numbers 37246 and 37247 in their United product line. I don't know what IH they actually fit; my search for them was centered on physical dimensions. Application info was secondary.

Jim

[Jim L.]

Re: 1962 brake advice

Did you replace your steel brake lines when you rebuilt your brakes? If so, how hard is to replace the line that goes under the engine?

No, and while I've "gotten away with it" for a couple of decades now, I wish I had changed the steel lines. I can't speak to the difficulty of changing the under-engine line, but if I were motivated to change it, I'd find a way.

Also, I am looking at converting to dot 5 but I am being told if I do that Apple (where I will send the Cylinders to) will not warranty them. They say that D0T 5 causes the seals to swell and leak ??? Have you ever heard of this?

I've heard of more than one brake rebuilder making such a claim but I don't know if there is any science behind it. My anecdotal experience leads me to conclude that such stories are toro-poo. All of my old cars have DOT 5 brake fluid in their systems and all of them have brakes that work perfectly. This even includes my vintage race car and my bride's track car (visible in my avatar). DOT 5 is so superior to DOT 3/4 that I'd void a warranty if need be to continue using DOT 5.

Jim

[Elwyn S.]

Re: 1962 brake advice

Jim,
Thank You for your insight and experience. I honed out the wheel cylinders and they will need to be resleeved. I have also ordered a complete set of steel lines for my car, with all the rust evidence showing up with the master cylinder and wheel cylinders I am sure the steel brake lines will show evidence of rust internally. I will post my experiences with replacing the lines after I am completed. Hopefully, someone else will chime in that has done this job in the past with thier experiences with the engine still in the car.

[Jim L.]

Re: 1962 brake advice

I'm always happy to share what I (think I) know, Elwyn. I'll be real interested in your experience with the job of replacing the steel lines.

Several years ago I made and installed a replacement for the tank-to-pump fuel line. My expectation going in was that I'd need to lift the body of my '60 to snake it into position. Nope. The old line came off and the new line went on very easily... no body lifting, no extra bends required. I would expect the long brake line to be similar. Of course the rear axle brake line is easy to change. So, the only "problem child" ought to be the under-engine line.

If you find a way to change it, I just might have to get out my benders and start making a new line for my car.

Good luck,

Jim

[Philip P.]

Re: 1962 brake advice

One question in looking at the cylinders on NAPA and Raybestos the input line thread is metric sized M10X1 compared to 7/16-20 which I believe is on 1 3/16 wheel cylinders. Just want to make sure what would be required.
Thanks
Phil

[Jim L.]

Re: 1962 brake advice

One question in looking at the cylinders on NAPA and Raybestos the input line thread is metric sized M10X1 compared to 7/16-20 which I believe is on 1 3/16 wheel cylinders.

I see the mention of metric threads on the 37246 cylinder. That's an error. The thread really is 7/16 and you can see that when you look at the 37247 cylinder. Remember, these wheel cylinders are for a vehicle that was made back in the pre-Metric days. The replacement parts need to conform to the original configuration.

Jim

[Joe L.]

Re: 1962 brake advice

One question in looking at the cylinders on NAPA and Raybestos the input line thread is metric sized M10X1 compared to 7/16-20 which I believe is on 1 3/16 wheel cylinders. Just want to make sure what would be required.
Thanks
Phil

Phil------


Some of the later GM replacement brake parts did go to some with metric thread. However, I don't know of any case where the TUBING NUT size went from SAE to metric. Usually, it would be things like attaching fasteners or hole sizes. Also, many of the later GM replacement wheel cylinders did use metric thread bleeder valves. This is no big deal, though. Who's going to be able to tell that the bleeder valve is metric thread?