P38 Brake caliper refurb

Hi All,

Just joined up and need some help, I'm not a mechanic just and enthusiastic amateur.

Front near side brake caliper leaking, have bought refurb kit (seals, boots etc) and have done this before on the other side .... but they are a real pain to refit the pistons .... is there a trick to this that anyone knows, I must be doing something wrong?

Best
Martin

Hi Martin

I'm probably not the best to advise, as this is a job I've not actually done on my P38 (though many times on other vehicles), but I am on line at the moment - incidentally, just put new discs and pads all round on mine, though didn't need to release any brake-pipe joints (or remove pistons) I pressed the piston back with a 'G' clamp.

There will likely still be back-pressure in your system, albeit a lot of air in it by now. This could put up a fair amount of resistance to pushing that piston back in, unless you have taken the caliper off completely, in which case it's just a question of perseverence: ensuring internal surfaces are as polished as possible (with nothing stronger than a cotton cloth in my view). Of course, once you're sure the piston is centred properly you could use a 'G' clamp to press it home.

Best I can do I'm afraid - as a 'gifted' amateur myself (which I'm sure you are) who has been doing his own mechanics for well over forty years now.
Regards
DougK

Thanks Doug.

Will be taking caliper off (as I did last time) but getting the pistons in and parallel with the dust boot and the o ring seems to be the problem, cant see anyway around it .... used a G clamp last time to try and exert even and direct pressure ... just thought I must be missing something. Thanks for the prompt reply anyway.

Cheers
M

Use plenty of brake fluid as a lubricant when you're putting them in. Helps enormously.

Thanks Derek, did try to, even tried a bit of vaseline but .... I am right in saying that you cant get the dust boot on after the piston is in the cylinder, ie it has to be all done in one action.
M

Sorry M, it's been some time since I did one but I'm sure the piston has to be in the caliper before you can get the dust seal on. Someone who's done one a little more recently may be able to help you better.

Thanks Derek,

If anyone has done one recently I would really welcome their input on this as I cant see how to achieve this ... maybe its my age