Brake Caliper Overhaul Kits

[grae35]

Brought off ebay from japan front and rear brake caliper overhaul kits primarily to replace the rubber piston boots which cop a caning from heat generated I suspect on track days. Thought there would be no harm replacing the piston seals also as they are probably hardened with age and heat as well.

Only problem is the parts packets are labelled in japanese and I am unsure about the grease sachets included.

The front kit came with one sachet of pink coloured grease. The rear kit with two smaller sachets of pink/orange grease and one white/beige grease.

My question is what exactly is the grease for? I imagine that one is rubber grease for the seals and boots on reassembly but not sure why I have three different types in the two kits. Guesiing that maybe the whit/beige is for the slide pins?

Anyone used these kits before or know which grease is which???????

I have emailed the supplier but so far have not heard back.

[grae35]

In the absence of any replies from supplier or other sources I bit the bullet and did some google research. Brought a tub of penrite red rubber grease from autobahn and some permatex slide pin grease from supercheap and left the supplied unknown sachets unused.

The job wasn't too bad. A bit fiddly reseating the new boots in the caliper cylinders but the seals and slide pin rubbers are dead easy.

For anyone who is interested my caliper seals were in perfect condition. No observable wear or for that matter on the pistons or cylinder bodies. The car has done 87K and quite a few track days/ happy lap sessions etc.

Probably the only lesson to be learnt is go easy on the non brembo brakes on the track. Give them plenty of cool down laps. And if you do perish your dust boots from excessive heat. They are replaceable with the overhaul kits available.

[R6n350GT]

im about to rebuild a set of AP Racing brakes i got to replace the Brembos. They suggest soaking the seals in break fluid and then installing. where did you use the grease exactly ?

[grae35]

Hi Nate

My manual also said to coat seals and boots. It said to use either rubber grease or brake fluid on the seals. I used rubber grease and would recommend it as seems to allow pistons to go in more easily than just the fuid. The tolerances on caliper to piston are quite small and the grease seemed to be prefered by most mechanics I consulted via google. I just used my fingers to lube all round seal and then push into place in the wheel cylinder housing groove they go in. However the dust boots were a different story, tried using grease as recommended on the inside of the boot but it made it such a slippery mess to then seat the boot in the cylinder and piston grooves that I gave up. Wiped off every thing and fitted boot dry over end of piston. Then put a smear of grease around piston before pushing into caliper cylinder with fingers and seating outer seal in piston groove. I used conmpressed air to carefully push piston back out half way to check boot was properly secured into housing.

Be careful using compressed air as it takes minimal effort to blast piston out of cylinder. Most manuals show operator puting a small wooden block in the pad space to cushion the blow of ejection. I forgot to do this once and tried using my fingers to catch the piston. Almost broke it and took skin off!