brake rebuild

[surfcity914]

I'm going to be rebuilding my calipers. I've purchased rebuild kits for the front and rear calipers from GPR, and would appreciate any advice on any pitfalls or things to be careful of when performing the rebuild. Thanks.

[Conrad W Peden]

I got a rebuild kit from someone other than GPR not that it matters....But, the ring clips that hold the boots to the caliper housing were the wrong diameter for the rears. It wasn't a problem seeing as the old ones were in good condition but if yours aren't you might want to check to be sure. Before you have a disassembled caliper and have to wait days to put it back together.


Conrad
72 L20E in rusto.
73 L20E in resto. http://members.rennlist.com/a914lover

[Pritchard]

Just out of curiosity, when do the calipers need to be rebuilt? I guess a better question would be what symptoms of wear should I be looking for?

Mine are working fine now, but with them being 26 years old, I'm sure that they will need rebuilding sometime.

Thanks

Pritchard

[surfcity914]

I have to rebuild my rear calipers because they are leaking at the parking brake vent clearance adjuster. I figured that I should do the fronts also since they're the same age. For me, it's just peace of mind for safety reasons. When I step on the brake pedal, I want to be confident that the braking system is working properly.

[JP Noonan]

Not to argue with a man such as Brian, but I've allways heard you should never split the calipers on any car. I didn't need to when I rebuilt mine, it would have made things easier no doubt, but I worried about getting the two halves aligned and torqued together correctly.

[surfcity914]

Brian, when you say to blow out the pistons with compressed air, do you mean a can of compressed air? Do you simply place the nozzle to the brake hose connection and blast it with air?

[efeinsmith]

When they say "compressed air", it usually means from a compressor. You need to do one side at a time because once one piston is out, you won't build up enough pressure for the other one. Also, NEVER put any part of your hand between the pistons when you blow them out (use a piece of soft wood) because they will pop out with CONSIDERABLE force and crushed fingers are no fun.

If they are stuck, you can use a grease gun attached to the inlet to pop them out. Cleanup will be a mess, but I has a pair of A calipers and that was the only way to free up a stuck piston. Just remember to clean all internal passages very well to get the grease out.

[JP Noonan]

I would say it would be much easier to split them, it allows a better angle to clean up the bores. If Brian has done it than it should be O.K. Most of my previous experience has been with cast iron domestic "floating" single piston calipers. I could be they aren't made as well as the ATE aluminium ones the 914 has.

Anyway, if you mean the vent clearence adjusters, I simply turned them with an allen wrench until the piston moved as far as it would. Then I removed the cir-clip and 13mm jam nut. On one side I could then pull the pistons out by hand and then the adjuster screw came out. On the other side I had to screw the adjuster back in and push the allen wrench into the adjuster to free the piston.

On the rears I didn't use compressed air, and I don't thnik it will help. The adjusters mechanically hold the pistons in.