Reconditioning mk4 rear calipers

[Rpmayne 0]

I recently bought some mk4 calipers mail order from a scrap yard and of them had a badly cracked piston seal, and subsequently had seized. Quite ironic really seeing I bought them so I wouldn't get that.

 

Anyhow, can this be cured with an overhall (if so, any tips) or shall I just tie them to a brick and hand return them?

[dinkus 10]

I think you can buy caliper overhaul kits from VW which include all the seals, but I'm not sure how much they are.

[dr_mat 0]

I hope they were cheap!

[Rpmayne 0]

£50 the pair, thought they should have been usable for that money. Said they would take them back but after the faffing about sending them etc it will probably be cheaper to just recondition them. At least then I'll know they're both ok.

[Roger Blassberg 0]

I have just re-sealed a pair of 288mm ATE front calipers, as a precaution before fitting them; the seals cost about £11 per side at VAG. There is a main seal in the bore of the casting and a bellows-type dust seal. Its a fiddly job but requires nothing more than patience.

 

BUT, if the piston is seized because the dust seal was damaged, there is every chance that the surface treatment of the cylinder and/or piston has been damaged by corrosion. In that case there is nothing much you can do except to make it into a tastefully unusual paperweight

 

Sorry if I am asking an obvious question, but are you sure that it is siezed? On a rear caliper you have to wind the piston in or out - it won't just press in.

 

Best wishes

 

RB

[Rpmayne 0]

It's not completely locked but is very hard to wind in compared to the one with the good seal. Think I'll be returning them then to save mucking about. The original mk3 ones are working anyway so will just leave it alone. Thanks.