63 Wheel Cylinder Numbers

[John F.]

Can someone tell me what the correct/original wheel cylinder numbers are for all 4 wheel cylinders on a 63? Every year for the last 3 years I've had one start to leak due to moisture buildup and eventually they rust then leak. I've decided to replace everything, lines, hoses, etc and switch over to Dot 5 so I'm trying to decide, do I get the old ones I saved (that might be original) sleaved with SS or Brass? or do I just buy new ones from the local auto parts store? I'm planning to have the car judged someday and I'd like to keep it as original as posssible but according to the judging manual the wheel cylinders are not judged and it doesn't look like the bleeder valves are either. the car might see 500 miles per year and I live in Ohio if that factors into your opinion. Looking for any advice on how to make the switch over from Dot 3 to Silicone Dot 5 too.

thanks so much

JF

[David L.]

Re: 63 Wheel Cylinder Numbers

My 1963 Chev.Parts Catalog (Oct. 1962) lists the following for the Wheel Brake CYLINDER ASSEMBLY in Gr. 4.655:

60-63 PASS., CORVETTE........front, left (1 3/16" dia., cast 5459465)..........5459516
60-63 PASS., CORVETTE........front, right (1 3/16" dia. , cast 5459466).......5459517
59-63 PASS., 63 CORVETTE....rear (right and left) (1" dia.)........................5459918

No casting number given on the rear cylinders.

Dave

[Duke W.]

Re: 63 Wheel Cylinder Numbers

You could rebuild/sleeve the OE wheel cylinders, but given that they can't be judged, it doesn't make economic sense. Functional replacements are inexpensive. The reason they are leaking is corrosion due to moisture absorption by the conventional glycol brake fluid. If the system have been flushed ever few years over it's life, they'd probably still be okay.

Silicone fluid will virtually eliminate moisture absorption, but because DOT 5 silicone is not miscible or compatible with glycol based fluid you must remove every last molecule of the glycol based fluid.

If you buy new wheel cylinders, disassemble them, clean in denatured alcohol and reassemble them with DOT 5 fluid... same applies to the master cylinder.

Flush the new brake hoses with denatured alcohol because conventional brake fluid is used as a lubricant when the ends are swagged on.

Also flush with denatured alcohol and thoroughly dry all the brake pipes.

Now you can install everything and fill/bleed with silicone fluid. and you should have a very long lived system.

I still recommend a brake flush every ten years or so. Silicone fluid will not absorb water, but if any gets in it will form a slug that will cause local corrosion, however, this is more of an issue with disk than drum brakes since the wheel cylinders in the drum brake system are protected from direct water splash.

Duke

[Gary F.]

Re: 63 Wheel Cylinder Numbers

Attached pic is of Service replacements, but they show the casting numbers.

[Harry S.]

Re: 63 Wheel Cylinder Numbers

The rears have the same casting number but they are physically different, they are not interchangeable side to side.

[Dan B.]

Re: 63 Wheel Cylinder Numbers

I decided to have my originals SS sleeved. Even though they can't be seen, FUNCTIONALLY no more rust issues to deal with. I personally think it's worth doing. They SS sleeve calipers, why not the wheel cylinders as well on drum brake cars. True, you could buy replacements for a lot less, but how many times do you want to deal with on going brake issues? Dan

[Stuart F.]

Re: 63 Wheel Cylinder Numbers

Living here in Florida we have a great problem with this due to our heat and humidity. I lost my originals to water and corrosion (actually just the right front). My sintered metallic linings were also losing their pads due to rust, so I opted to change to metrix ceramic linings and change to new cylinders, all hardware, hoses and a sleeved master at the same time.
In talking with a number of old time Floridians at car shows I learned that many of the guys with old drum brake cars, that see typical show car use, prefer to just use Dot 4 instead of going to Dot 5 silicone. They claimed it lasted longer than Dot 3 and therefore only needed changing every 4 or 5 years. Well, I now have mine using Dot 4 and it has been about 4 years since I made the change. My brakes still work real good, but I try to take the car out for exercise every Sunday morning so it never sits too long. Still and all, this past summer was brutally hot and humid so I'm going to do a flush soon now that the weather is cooler. One thing I also learned is they never use fluid from a previously opened can, rather use a new "sealed" container. I guess the containers don't have good shelf life once opened.

Stu Fox

[John F.]

Re: 63 Wheel Cylinder Numbers

Thanks for all the replies. Is it possible to clean/flush the existing brake lines with denatured alcohol too or am I just looking for trouble if I don't replace the brake lines, hoses and blocks? The entire system is drained of the Dot 3 now but obviously there is still some left in the master and the lines. I'm tired of replacing wheel cylinders every couple years so I'd really like to get over to silicone but it seams like such a difficult task with the body on the frame replacing brake lines.

[Duke W.]

Re: 63 Wheel Cylinder Numbers

Read post #3.

In addition you should thoroughly inspect the brake pipes for exterior corrosion. GM didn't design these cars to be in service for 50 years, but corrosion effects vary widely with climate and use.

Replacing suspect brake pipes on a '63 should be easier than on later years that have screwed on clips. The '63 brake pipe clips are not bolted but "spring" into the frame holes and pipes, however, lifting the body a couple of inches always makes the job easier.

Duke

[John F.]

Am I missing anything? Overlooking something? Is using compressed air at the MC brake line connection the best way to get air into the system?

Thanks so much for your help.

[Duke W.]

Re: 63 Wheel Cylinder Numbers

I recommend some changes to your plan.

1. Remove the M/C and all wheel cylinders.

2. Buy some vacuum caps or make some from suitable size rubber or Tygon tubing that will fit snugly over the flares at the end of the pipes, which I expect will be 1/8-3/16" ID.

3. Rig up a siphon with a hose from a high mounted container to the M/C brake pipe, and make four hoses long enough to extend from the wheel cylinder brake pipe flares to a container.

4. Install the plugs at the ends of the brake pipes on all four corners.

5. Start the siphon then go to one brake pipe, remove the plug and install the hose to the container. Wait until you get a clear stream of fluid, then remove the hose and replace the plug.

6. Do the other three. It really doesn't make any difference where you start and where you end, although some guys will claim if you don't use a certain sequence the sun will not rise the next morning.

7. Go around two to three times. You can even leave the alcohol in the system overnight between rounds.

8. Once you are convinced that all DOT 3 is flushed, remove the siphon and plugs and let the pipes drain for at least an hour, but overnight is better.

9. Once the pipes are drained blow a lot of compressed air through the pipes well beyond where the exits show no signs of liquid. You might do this over a period of days. If you have a vacuum pump draw a vacuum on the pipes as this will help vaporize liquid. Even a Mity Vac will help. How much time you spend on this depends on climate. The pipes will dry much faster in high temperature, low humidity than low temperature high humidity. It would also help if the compressor has a moisture trap like used for spray painting.

10. While you're working on flushing and drying the brake pipes disassemble, clean with denatured alcohol, and inspect the M/C and wheel cylinders to decide if you want to rebuild or rebuild or replace them. If you rebuild, assemble them with DOT 5 fluid. If you by commercially rebuillt of new you MUST DISSEMBLE THEM, CLEAN WITH DENATURED ALCOHOL, AND REASSEMBLE WITH DOT 5.

11. Bench bleed the M/C with DOT 5.

12. Filling/bleeding the system is a matter of choice. I prefer getting a helper to pump the pedal while I operate the bleed valves, but everyone has their own preference.

13. Be careful when pouring DOT 5. I has more tendency to trap air bubbles. Hold the can low to the top of the M/C and pour slowly. Also, use a small hammer to tap the M/C and inspect the reservoir for air bubbles before you continue bleeding.

Duke

[Gerald C.]

Re: 63 Wheel Cylinder Numbers

Dan,

Who did the SS sleeving for your wheel cylinders?

Jerry

[John R.]

Re: 63 Wheel Cylinder Numbers

Rear cylinder castings are 649. As Harry said, same cast but there is a RH and LH version of each.

[Dan B.]

Re: 63 Wheel Cylinder Numbers

Dan,

Who did the SS sleeving for your wheel cylinders?

Jerry

Jerry,

Brake & Equipment Wharehouse in Minneapolis, MN. Great to deal with and they can also provide you with the proper Raybestos rebuild kits at a reasonable price as well.
This thread is almost 7 years old and I have still not had to touch those brakes since the install which was back in 2009

[Harry S.]

Re: 63 Wheel Cylinder Numbers

Jerry,

Brake & Equipment Warehouse in Minneapolis, MN. Great to deal with and they can also provide you with the proper Raybestos rebuild kits at a reasonable price as well.
This thread is almost 7 years old and I have still not had to touch those brakes since the install which was back in 2009

What Dan said. They do a great job......