beefey

I'm not all that familar with fixed calipers, all I've ever worked with is floating so I was wondering is it common to have one pad totally worn and the other with WAY more material still left on? Does this mean one side of pistons are shot? Is there a good way to diagnose a bad caliper?

Thanks,
Beefey

beefey

um Bump?

-Thanks
Beefey

Tom M'Guinn

That is not normal in my experience. I woul check to make sure everything is moving as intended. Sounds like something is hung up somewhere.

jasonlp

you might have corrosion behind the aluminum guide warping it

eclou

I just had this problem. 2 of the "spring plates" that guide the pads were warped from heat and corrosion. You can buy replacement parts from Porsche for about $20

insite

FYI, this can also be caused by worn out seals. the EPDM square seals that prevent fluid from passing the piston are ALSO responsible for retracting the pistons slightly when you release the brake. if the seals have been overheated, they have likely lost duro (softened) and can no longer retract the pistons. this results in a cycle whereby the pads drag & create heat, worsening the problem. one of the symptoms is uneven pad wear from inboard to outboard.

try the spring plates according to eclou; if that doesn't work, it's time to rebuild the caliper.

eyeball kid

Not to hijack the thread, but you mentioned rebuild, and I've been thinking it's time to rebuild mine. Does anyone have experience with rebuilding the stock 951 brakes. Is paragon the best place to get rebuild parts? Does anyone have the list of needed parts for the rebuild

insite

pelican usually doesn't stock the inner seals. i've never rebuilt 944 calipers, but i've done a lot of 996 & boxster calipers. i get all my parts either at http://www.zeckhausen.com/Brembo/Con...es.htm#Rebuild or at www.hrpworld.com. the rebuild's pretty easy; just remember to soak the inner seals in brake fluid for 30min prior to assembly.

Tom M'Guinn

I did my 86 951 calipers last year. After checking all the usual suppliers, I could only get the rebuild kits from Porsche and they weren't cheap!

eyeball kid

Any one have a part #s list?

beefey

When you speak of spring plates do you mean the things on top of the calipers that look like a cross that hold the pads in? You can buy aftermarket ones?

Also what goes wrong with the caliper, how do they fail? They seem REALLY simply being only pistions, a couple o-rings and the casting. Hopefully the casting doesnt warp and the pistons well I dont know how they would go bad so that leaves us with the seals... People pay 500+ dollars for a caliper when their only flaw is the seals?

Pretty confused here
Beefey

eclou

spring plates are the removable silver sleeves that guide the pads in place. They "line" the caliper and sit on the 2 interior faces of the caliper where there are not pistons (fore and aft). They can warp and thus bind the pads