[captaindagman]

Hi all,

Can anyone tell me how to remove a split gaiter on a rear caliper piston and fit a new one ?

Cheers

[nzenigma]

You will need to move the piston out of the cylinder. The dust cover (gaiter) fits into a recess on the piston so it can be stretched quite easily for removal and replacement.
Ideally, you should remove the calliper from the vehicle. Push the piston back with a  'G' clamp to remove brake fluid, then carefully apply air pressure to push the piston back out. This helps keep everything dust free.
A side of the road method is to unbolt the calliper with brake hose still attached, remove brake pads, then gently push on brake pedal. The piston will be pushed out far enough for you to proceed as above.

[captaindagman]

Thanks for that.  I'll be doing it roadside.   I can see how pushing out the caliper enables the gaiter to be disconnected from the piston.  How do you get the other end of the gaiter out of the caliper body ?  How do you get in there with the piston in place ?  Does the piston go so far in that you can get to it ?  Does it have a circlip ? 

All comments gratefully received.

[captaindagman]

I've answered my own questions.
Bought a piston boot for Hyundai main dealer today. The parts guy said " push the piston in all the way and you will be able to reach the boot which sits in a groove inside the cylinder ".

Totally wrong !  It is a long piston and stands about 6mm proud of the cylinder when pushed in all the way. In fact, it is the piston that keeps the boot in place.

The only way to remove the old boot is to force out the piston by using the brake pedal, pull the boot off the piston and then take the piston right out . That is the only way you can get the boot out of the groove in the cylinder.

The cylinder has a bit of rust around the lip and even after cleaning it up it makes it difficult for the new boot to slip into the groove.  After many attempts I found that you have to stretch the new boot over the bottom end of the piston and then insert it into the cylinder and try to get the boot lip into the groove in the cylinder. Eventually it seemed to seat properly and I was able to push the piston in all the way and get the boot to seat in the groove in the piston.  Then it is just down to replacing the caliper and bleeding the system.

To sum up a very frustrating waste of time for something which should be so simple.  Next time I will get my friendly mechanic to do it for me.

[Shambles]

good one, skip

[nzenigma]

To sum up a very frustrating waste of time for something which should be so simple. 

Ive found everything is simple next time.  Don't give up on the adventure.