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Jaguar 420 Caliper rebuild?

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PlaidMan

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After changing the front brake hoses , it did not take long for the front calipers to develop a leak. Have new seals and pistons and have removed the old parts and cleaned the calipers. Am ready to install new seals and pistons and was wondering if there are any tricks to installing the pistons(3 of them) in the calipers? Seems to be a little tricky installing the dust seal and trying to push the piston in all at the same time.

Thanks, Charlie
 
I split the caliper in half. D
o not loose the small seal that seals the halves. Put the seals in, make sure that you have them right way around. Then fit the dust cover. Lube the cups with Girling red grease and press in. Fit the small seal to one half and replace the bolts. What ever you do, do not place the caliper in a parts dip or carb cleaner tin...this will perish the small seal.
Cheers,
D.
 
Well I did not split the calipers but with a lot of fiddling was able to fit the seals, dust cover and then the pistons using brake fluid as a lubricant. Had to use a C-clamp to install the pistons, somewhat difficult to keep the larger piston to stay aligned as I pressed it in. After installing on the car had a bad leak from one of the large pistons. After disassembly found I had torn the seal ring upon installation of the piston. Wish I had some of that Girling red grease but as I'm using Dot 4 maybe there is another type of grease I could use in its place.
Thanks for the info D.
 
No worries. I am not fond of brake fluid for assembly puposes, but it does work as a last resort. I would only use Girling grease....all of the big supply companies have it on hand.
Cheers,
D.
 
Always remember that if the piston doesn't go in by hand pressure, then something's probably misaligned. All the Girling calipers I've done for other cars, only takes easy pressure from a couple fingers on each hand.
 
Recieved a new caliper kit today and as MikeP said I tried very carefully to press in the piston with only finger pressure(the 2 small pistons went in easily but not the larger one). Well, all I can say is that caliper piston gave me the finger back every time I tried, finally had to use 2 c-clamps working slowly trying to apply even pressure and that took some doing until it passed the lip of the seal. Whew, it must have something to do with the thickness of the seal itself, not sure who the manufacturer is of that seal kit but I think that is probably the problem. Thanks for your help, Charlie
 
I have run into some where the seal has been very slightly undersize, QH kits mostly. My biggest concern when it's difficult to get in is will it retract propery after you take your foot off the pedal.
 
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