Lost A Seal When Rebuilding R33 Gtst Calipers :(

[S3RK]

Hi guys/girls,

a few weeks back my front-right caliper started leaking fluid from the top outer piston, so obviously time for a rebuild...

Got my kit today and first time ever opening up calipers, followed a rough guide and managed to pop all the pistons out using an air compressor, replaced all the seals, but the only seals the rebuild kit didn't come with are the 2 small ones ( 8mm wide, 6mm hole, 3mm thick approx. ) I managed to have lost one when popping the pistons out. It is one of the the seals (or O-ring) that sits between the caliper split, where the fluid passage is, I went to supercheap/autobarn/autoone/bursons, and none of them supplied or could get them, the closest thing I could find was in an O-Ring assortment which is the exact same size and fit, but it is round rather than flat edged (or square O-Ring if you will).

I've fitted it on now but I'm not entirely convinced it will work as I'm still yet to bleed the system and actually test it out, but for peace of mind sakes I'd still like to get some and fit it. Does anyone know the exact measurement and/or where I could get some? I would really appreciate if you could help me out!

Thanks in advanced!

[Greekos]

It's ur brakes dude go buy another kit and fix it right $50 For seals is cheaper than losing ur brakes

Edited June 11, 2013 by Greekos

[Daleo]

I would not even think about using that caliper without the correct o-ring in place.

Sadly none of the replacement sumitomo seal kits I've ever seen contain that particular o-ring.

[GTSBoy]

There's a place about 2500m from my office that specialises in selling just o-rings and o-ring type seals. You should look for a similar place, using.....I dunno, something like the yellow pages.

[S3RK]

It's ur brakes dude go buy another kit and fix it right $50 For seals is cheaper than losing ur brakes

As #@Daleo said, that specific O-Ring is NOT included in any of the kits as Sumitomo strongly advises you don't split the calipers. I've found a website http://www.mcmaster.com that definitely has the O-Ring I'm looking for (going by other forum posts, unfortunately they don't link the specific one or mention the measurements), so now I'm just looking for the measurements and I'll order them in ASAP.

If I can't find the measurements or no one knows, I'll measure them myself tomorrow night.

Thanks though guys, really appreciate it!

[Greekos]

i have split calipers in the past, make sure you dont damage the machine surfaces and torque them up right and they should be fine, get the right seals and it should be good and just makes sure u test the brakes well!! what brand of seals do you guys use, Nissan?? the seal kit i got last year seemed like the dust seals were less of a quality than the factory ones i pulled off.

[Daleo]

The last set of Sumitomo's I stripped; ended up re-using the seal kits as they were in such good nick.

[Greekos]

cool, where did you get them from??

[Daleo]

cool, where did you get them from??

They were just a lucky Ebay find; the guy was using a GT-t front cut to re-power an R31; and had no use for the brakes.

I think they'd done very little work. You can buy OEM seal kits; so they should be fine; they just don't contain the sandwich O-ring.

If you took a sample to an industrial Hydraulics Specialist (not Pirtek) that does work with large valve banks and the like; they might be able to match it up.

[S3RK]

Well the sandwich one is the one I'm looking for

But nonetheless the rounded O-ring I put in there as a temporary replacement is holding up very well. Not one sign of failure/leaking!

[Daleo]

I guess you won't really know until it happens. And at that point it may be too late.

Did you soak the O-ring overnight in brake fluid prior to installation; to ensure it wouldn't swell/degrade?

[S3RK]

I guess you won't really know until it happens. And at that point it may be too late.

Did you soak the O-ring overnight in brake fluid prior to installation; to ensure it wouldn't swell/degrade?

That would of been a good idea...