1965 Brakes....

[Brian Stephens]

This message was prompted by a statement is another message about bleeding brakes. If you have two good calipers (non/ss) and two that are starting to leak after 18 years of sitting, would you be better off to rebuild what you have and see how they work or go ahead and buy a staninless set? I am only asking because the concensus in the other thread is that routine bleeding, cleaning, and inspections should be done on both stainless and non stainless brakes.

An thoughts?

[Joe L.]

Re: 1965 Brakes....

Brian----

This should be an easy one. If I were you, I'd remove all of the calipers from the car. Disassemble and inspect the caliper bores. If the caliper bores are not pitted and can be cleaned up with crocus cloth, you don't need to have them sleeved. However, if at least one bore on any caliper is not serviceable, you will need to have that caliper sleeved in its entirety. If you end up with 3 calipers that need to be sleeved and one that doesn't, I'd probably go ahead and have all 4 done.

If you get lucky, which is unlikely, and all 4 of your calipers are rebuildable, as is, replace the piston seals and boots. Usually, with brakes as old as yours if they're original, you will also need to replace the pistons. Pistons should always be replaced if there exists ANY wear on the skirt and sealing ring of the piston. That means if the anodize is worn through at any point in this area, you need to replace the pistons. However, there is a complication if you have the original 65-66 Corvette calipers. These calipers, referred to as "1st degign", differ from the later 67-up "2nd design" calipers in two ways. First, the calipers have a cast-in piston guide in the back of the bores and the pistons have a reduced diameter rear extention which fits within the guide. Second, first design pistons are fitted with a "Pyroceram" insulator which attaches to the face of the piston with a central phillips head screw. The "Pyroceram" insulator was supposed to reduce the heat transfer to the brake fluid. These insulators were also used with "2nd design" caliper/pistons for the 67-75 J-55 HD brake system.

The problem for "1st design" brake owners is that the pistons and insulators have been long discontinued by GM. The insulators are usually not a problem since, in general, they are serviceable. The pistons can be a problem, however. I believe that these pistons are available in reproduction from Dr. Vette, Vette Brakes and Stainless Steel Brakes Corp. However, they are EXPENSIVE, as they were when still available from GM. I belive they sell for about $25+ each. That's $400 for the set of 16. As far as I know, no one reproduces the Pyroceram insulators.

Most brake caliper rebuilders, when they come across "1st design" cores, machine out the cast-in piston guides and convert the calipers to the "2nd design" configuration. They then use the "2nd design" non-guided pistons without Pyroceram insulators. That, of course, would remain an option for you. Any of the caliper rebuilders mentioned can sleeve your existing calipers and maintain "1st design" configuration. However, the cost of the rebuild, including new pistons, is considerably more than "2nd design".

If your calipers have been previously replaced, all of this will be moot. The chances then are that you will already have the "2nd design" calipers.

[Joe L.]

Re: 1965 Brakes....

Brian----

This should be an easy one. If I were you, I'd remove all of the calipers from the car. Disassemble and inspect the caliper bores. If the caliper bores are not pitted and can be cleaned up with crocus cloth, you don't need to have them sleeved. However, if at least one bore on any caliper is not serviceable, you will need to have that caliper sleeved in its entirety. If you end up with 3 calipers that need to be sleeved and one that doesn't, I'd probably go ahead and have all 4 done.

If you get lucky, which is unlikely, and all 4 of your calipers are rebuildable, as is, replace the piston seals and boots. Usually, with brakes as old as yours if they're original, you will also need to replace the pistons. Pistons should always be replaced if there exists ANY wear on the skirt and sealing ring of the piston. That means if the anodize is worn through at any point in this area, you need to replace the pistons. However, there is a complication if you have the original 65-66 Corvette calipers. These calipers, referred to as "1st degign", differ from the later 67-up "2nd design" calipers in two ways. First, the calipers have a cast-in piston guide in the back of the bores and the pistons have a reduced diameter rear extention which fits within the guide. Second, first design pistons are fitted with a "Pyroceram" insulator which attaches to the face of the piston with a central phillips head screw. The "Pyroceram" insulator was supposed to reduce the heat transfer to the brake fluid. These insulators were also used with "2nd design" caliper/pistons for the 67-75 J-55 HD brake system.

The problem for "1st design" brake owners is that the pistons and insulators have been long discontinued by GM. The insulators are usually not a problem since, in general, they are serviceable. The pistons can be a problem, however. I believe that these pistons are available in reproduction from Dr. Vette, Vette Brakes and Stainless Steel Brakes Corp. However, they are EXPENSIVE, as they were when still available from GM. I belive they sell for about $25+ each. That's $400 for the set of 16. As far as I know, no one reproduces the Pyroceram insulators.

Most brake caliper rebuilders, when they come across "1st design" cores, machine out the cast-in piston guides and convert the calipers to the "2nd design" configuration. They then use the "2nd design" non-guided pistons without Pyroceram insulators. That, of course, would remain an option for you. Any of the caliper rebuilders mentioned can sleeve your existing calipers and maintain "1st design" configuration. However, the cost of the rebuild, including new pistons, is considerably more than "2nd design".

If your calipers have been previously replaced, all of this will be moot. The chances then are that you will already have the "2nd design" calipers.

[Brian Stephens]

Re: 1965 Brakes....

Great information, Thanks. I think my best bet is to purchase one of the complete kits from someone like Vette Brakes & Products Inc. that containes all the new lines and callipers.

[Brian Stephens]

Re: 1965 Brakes....

Great information, Thanks. I think my best bet is to purchase one of the complete kits from someone like Vette Brakes & Products Inc. that containes all the new lines and callipers.