Urgent Caliper Help

I have my front caliper in pieces at the moment:sos: now I have cleaned everything up but how the hell do you put it back together, does the rubber seal and retaining ring go in first or do you put the seal on the piston first, I have tried every thing and dont want to damage the new seals

PM DB! or msn his, he will help as he recently did this

I have my front caliper in pieces at the moment:sos: now I have cleaned everything up but how the hell do you put it back together, does the rubber seal and retaining ring go in first or do you put the seal on the piston first, I have tried every thing and dont want to damage the new seals

uk or j spec

J-spec, front twin pots

J-spec, front twin pots

well if you get stuck i have 2 fronts spare

I've never taken a J-spec caliper apart, but on the UK spec, the rubber seal goes on the piston first, then the dust seal goes around the piston and the retaining clip hold the seal to the caliper. - It's bloody messy and fiddly!

The rubber ring seal goes into the housing first, then you use the grease in the refurb kit to lube it and slide the pistons in. Fill the inside of the rubber dust seal with more of the pink grease and pop it over the end of the piston, and then press the outer edge into the recess in the top of the piston housing. Finally, fit the circlip into the groove in the dust seal.

Nice one Digsy, very easy once you know how, I had a stressful morning it was like something off the krypton factor.. thanks

thats handy to know as i'm going to be refurb my uk's soon

Is there some kind of step by step guide somewhere ?

After Digsy's help I thought I would take a few piccies

Parts required Piston seal, Piston, Dust seal, Dust seal retainer

Clean bore ready for piston

Fit piston seal

Slide piston into bore

Fit dust seal

Press seal into groove use something blunt as not to damage the seal (One of the utensils off her George Foreman wash it and put it away before she notices)

Slide retaining ring into outer ring of dust seal

Job done

Nice one. PMSL at your George Foreman seal insertion tool!

Did you do the "hang on these seals are far too big for the pistons" double take before actually trying to fit them, like I did?

Hold on a moment.....

On my J-spec fronts the calipers sit in a separate aluminium cast housing that bolts onto the slider. Those look like they are one-piece iron jobs, like my rears. Are there two different designs?

 

Did you do the "hang on these seals are far too big for the pistons" double take before actually trying to fit them, like I did?

Very much so, thought I had the wrong kit:)

They are front calipers off a 97 NA, and as you say cast iron.. I dont know much about the different specs between models but these once removed from the caliper hanger have four male torx bolts so they can then be split in two

Hold on a moment.....

 

On my J-spec fronts the calipers sit in a separate aluminium cast housing that bolts onto the slider. Those look like they are one-piece iron jobs, like my rears. Are there two different designs?

yes.

I take it you have to bleed the system first before you can do this?

Nice one Nick I've poached that for the FAQs

http://www.mkivsupra.net/vbb/showthread.php?t=107717

-Ian

if my caliper is off the car for refurb, do i just leave the brake pipe to one side? will it drain all the fluid out?

if my caliper is off the car for refurb, do i just leave the brake pipe to one side? will it drain all the fluid out?

It will yes, if that's a problem for you (although I can't think why it should be) you can buy a brake hose clamp and clamp the hose off. DO NOT clamp braided hoses, only rubber ones. You can also seal the banjo with an ordinary nut and bolt and the original copper washers. Renew the washers when you put it back together though.

Hi CW, I got these pads of you a while back and have not have time to change them until now the caliper is a bit sticking, might as well do it all, new pads, new seals, painting.

tango

bumping this as its a great guide and i want to know how easy the piston should slide in and out of the bore after a refurb like this?

I had a bit of hassle removing a piston today however the bore and piston were very clean. Still I cleaned off the old grease, regreased and test fit it back in a ways but i could not then pull it back out by hand.............is this normal? I think it was the rubber seal causing the problem does it swell with age?

Yes it should be tight even when newly fitted, if it wasnt the fluid would blow past the seal. The recommended way to remove is with compressed air. getting them out by hand is a real pain as you cannot be sure you are applying a consistent straight pressure so the piston may then squint in the bore . Just did one on a four pot front and the only reason i did it by hand was because i knew i was replacing the piston and seal.

cheers, I guess i just thought it would move a bit easier even though its a tolerance fit, i'll make sure i'm ready to fully reassemble the next time i pop them back in!