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Caliper rebuild

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DaveGT6

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I'm finishing up the rebuild on my calipers. I was surprised at how good they were all things considered (brake fluid was more like rusty water). I've needed to replace only one piston because the surface was compromised by pitting and the cylinders are in great shape. The problem is I spent about 2 hours yesterday afternoon trying to get the new 'dust boot' seals on. I had only temporary success. The few times I was able to get the seal to stay on the lip around the cylinder it would slip off when I tried to position the retaining ring (or spring clamp). What's the trick to getting these on and keeping them on?
Thanks in advance for any help. It'll be greatly appreciated!
 
Somewhere in the archives are old posts describing this. In brief what I do is have the boot in place in the inside groove in the caliper, position the piston atop the boot and (with the opposite caliper opening blocked) introduce modest compressed air into the caliper. The air inflates the boot and it really wants to go up and around the piston. I use a little hook of rounded 12ga copper wire to help it pop on. At that point the piston can be pressed home and the boot lip seated in the groove in the piston.

Everything is slathered in brake fluid to ease it along. The first one may take a couple of tries but by #4 it really is a 10 second task.

Easier with a helper -- my wife 'mans' the air gun and knows just how much pressure it takes to make it happen.
 
I'm working on a 70 GT6. My problem isn't getting the boot to seat to the piston, it's getting it onto the caliper. The lip it mounts onto doesn't have a groove for it to seat into so it keeps slipping off (when I can get it on.
Again, thanks for the help. And I'll search the archives better too.
Dave
 
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