Master cylinder rebuild kits

[R N.]

Hello All,

I didn't have much luck searching the archives for the part numbers/sources for rebuild kits for some master cylinders I want to take a crack at rebuilding.

I've a casting # 5455509 m/c ('67 manual brakes) and a 5450346 m/c ('70 w/PB) that I what to rebuild. I would prefer to purchase a rebuild kit from someone like NAPA locally, but they are not much help without a part number.

Or maybe these kits are still available from GM? Can anybody help?

Also, any pointers or advise for a first time rebuilder is welcomed.

As always, thank you for the help.

[John H.]

Re: Master cylinder rebuild kits

Auto parts stores normally list rebuild kits by specific application, not by master cylinder part number or casting number.

The '67 Corvette used the same master cylinder for both manual and power brakes, and it had a DEEP hole in the rear piston; some kits come with seals only - Paragon and LICS have the kit that includes the rear piston. Paragon also has the kit for the '70 with power brakes, including the rear piston.

Once you get them disassembled, check the bore surface VERY carefully; any pits or scratches will ruin new seals in short order. I used to hone them years ago if they didn't look too bad, but I gave that up; if they're bad enough to require honing, I send them out for sleeving, which is a "forever" fix.

[Joe L.]

Re: Master cylinder rebuild kits

Hello All,

I didn't have much luck searching the archives for the part numbers/sources for rebuild kits for some master cylinders I want to take a crack at rebuilding.

I've a casting # 5455509 m/c ('67 manual brakes) and a 5450346 m/c ('70 w/PB) that I what to rebuild. I would prefer to purchase a rebuild kit from someone like NAPA locally, but they are not much help without a part number.

Or maybe these kits are still available from GM? Can anybody help?

Also, any pointers or advise for a first time rebuilder is welcomed.

As always, thank you for the help.

Kurt-----


Master cylinder rebuild kits for either of your master cylinders are no longer available from GM. However, they are available from other brake parts manufacturers. The Raybestos part numbers are as follows:

1" bore (1967 with either standard or J-50 power brakes)= MK472

1-1/8" bore (1967 with J-56 power brakes and 1968-76 with J-50 or J-56 power brakes) = MK501.

Auto parts stores ought to be able to cross-reference these numbers to whatever line they carry, if not Raybestos.

[R N.]

Re: Master cylinder rebuild kits

Thank-you John & Joe. Your help is appreciated.

[Jim T.]

Re: Master cylinder rebuild kits

R. Kurt I rebuilt the master cylinder for my 70 with power brakes this year. I bought a rebuild kit, bleeder kit, and hone from O'Reilly Auto Parts.
I tried the local NAPA, they did have a master cylinder rebuild kit for my 70 Corvette.
The master cylinder rebuild kit I got from O'Reilly is "Brake Best" from Springfield, MO Ozark Automotive Distributors. Part # MCK59092. The net price was $25.99 with a list price of $44.05.
The bleeder kit is helpful in bench bleeding the master cylinder. I bought a Dorman Help part #13911. I bench bled my master throughly. I capped my brake lines after disconnecting them from the master cylinder to protect the fluid in the lines. After installing the master cylinder I left the brake lines loose enough to drip brake fluid, with good drips I felt assured that the lines had filled with fluid and fully tightened them. I have done this a couple times before on my 68 and 70 and it worked well. Again I did not have to bleed the calipers to get out any air, brakes worked great without having to bleed the calipers and still do.
The hone I bought is really a brake cylinder hone. Did not see a master cylinder hone to purchase. It is a Lisle part #10500 and has two stones. I only needed to touch up a couple spots in my master cylinders bore. I dipped the hone in denatured alcohol and ran the hone quickly down and back up and stopped and dipped it again for another quick run. Did not take much hone work. Used denatured alcohol to clean the bore with clean old pieces of a cotton t-shirt.
I was surprised that master cylinder rebuild kits are scarce. The Car Quest auto parts store does not have them. NAPA's complete rebuilt master cylinder is less expensive than the rebuild kit I bought.
The Brake Best master cylinder kit has a complete assembled rear piston and seals for the front piston installation by you. Once you look at the seals installed on the the old front piston you will see really how easy it is to get the new seals installed correctly. Use brake fluid on them so they will slide easier.
Check you master cylinder kit you purchase before you leave the store. The first one I got had the plastic parts bag opened, I had them order another one.
Denatured alcohol works pretty good to clean the outside of the master cylinder for painting.

[Gerald C.]

Re: Master cylinder rebuild kits

Hi,

Where can I send my 1967 M/C to get it rebuilt?

Thanks,

Jerry