C3 - 75 Brakes

[Jim K.]

A friend of min bought a 75 recently and I gave him several catalogs and the latest Driveline to get him to join and buy the right manuals (assemble & maintenance). He needs to "do the breaks" and is getting confused by all the different Kits and prices. I have a 61 and have no clue what you guys go through with all that fancy disk break stuff I do know ss sleeving is big but can you give a solid axle friend some advice to share with a new corvett owner? Thanks guys!!!! (and girls!!!)
Jim

[Harmon C.]

Re: C3 - 75 Brakes

Jim Any driveline vendor is OK as they sell about the same parts. Just do caliper set,Hoses,and Master Cylinder if it is not a judged car. For judging save the original M/C for rebuild. The hard part is getting the air out. Lyle

[Chuck S.]

Re: C3 - 75 Brakes

Jim, C3 disc brake calipers are prone to corrosion in the bores. If the calipers have never been sleeved, they are probably overdue, but only an educated inspection of the bores will confirm. If the bores are pitted, simply replacing the piston seals will not be a long term solution.

Rotors with excessive run-out will tend to "pump air" into C3 brake systems with conventional OEM style seals, making it very difficult to keep a firm pedal. O-ring pistons are less susceptible to "air pumping", and installing calipers with corrosion resistant bore sleeves and O-ring pistons is the best option. The calipers are dated, but its doubtful anyone will ever see the dates. If the original calipers are in very good shape externally, you can have them rebuilt and returned to you rather than take the chance of getting someone else's pitted cores.

Master cylinders can also be rebuilt with sleeves. As Lyle said, the MC cast date is important if the car is ever to be judged. You can buy rebuilt MCs on an exchange basis, but if it were me, I would have the original rebuilt. This practice will keep the car more original, and enhance its value later when its sold. While its not important for a driver now, a correct MC will be difficult to find later.

Silicone brake fluid would help to eliminate the corrosion problems found in C3 brake systems, but conversion from conventional glycol fluid requires a thorough cleaning of the complete system to avoid contamination. Replacing the calipers and flex lines will help in this, but the brake lines still have to be thoroughly cleaned.

[Joe L.]

Re: C3 - 75 Brakes

Jim------

In addition to what others have said, I recommend that if the calipers are to be replaced with stainless steel sleeved units that one use only HIGH QUALITY units as manufactured by Stainless Steel Brakes Corporation of Clarence, NY, Carters Corvette of Livermore, CA, Vette Brakes of St. Petersburg, FL, or Dr. Vette of New Philadelphia, OH. There may well be other high quality manufacturers out there, too, but these are ones that I KNOW of. Their products are sold by high quality Corvette vendors.

Some of the "cheapie" rebuilt sleeved calipers on the market use inferior stainless steel sleeves, some of which are DECORATIVE stainless and not the type 304 or 316-L used by the high quality manufacturers.

In any event, the owner should check to see if the calipers have been previously sleeved. If they have, the calipers can be rebuilt by simply installing new pistons and seal kits. If they have not been previously sleeved, I can virtually guarantee that all four calipers will need to be sleeved or replaced with exchange rebuilt sleeved calipers.

ALWAYS replace the flexible brake lines when calipers are serviced.

[Dick W.]

Re: C3 - 75 Brakes

One needs to verify, if the calipers on his car have been sleeved, that the sleeves are actually stainless. There are e-cheapo rebuilders that are actually using carbon steel sleeves! When I was a Vette parts vendor, I inadvertantly took several sets as cores.

[Jim K.]

Re: C3 - 75 Brakes

Thanks to all of you. My friend has seen these postings and should be pursueded to join NCRS. Thanks for the help.
Jim