Caliper refurb

[rs6mick]

Been thinking of this for a while as my front calipers are looking a bit tired anyone have any ideas on how to repaint them I was thinking of stripping them and having them powder coated but it's a bit of a worry that I might mess them up any advice would be helpfull

[Ryan_Pestell]

If stripped fully and powder coaters know what there doing there is no reason for them not to be 100%

All seals and dust seals must be removed, piston bores protected, and properly cleaned afterwards to get all the grit out.

[Nobby]

Are you planning a full refurb or just a splash of paint on them?

I've refurbished around 10 sets of 4 pot brembo calipers (from 20vt, also used on Pug 406 and Focus RS) in my time and whilst its not hard to do, you need to be very patient and keep everything spotlessly clean inside the calipers.

I'm making some fairly massive assumptions that you can buy new caliper part from either Audi or a big brake retailer, but this should be the case.

Whilst I'm not 100% familiar with the calipers on the RS6 (hopefully I will be soon when I get one), refurbing them should go something like the following: If you are going to completely refurbish them from bare then this is whats needed.

- Before removing the calipers from the car, unbolt them from the mountings and remove the pads. Cable tie them to the suspension so they don't hang from the pipes and damage them.
- With the help of someone apply the brakes very lightly and so the pistons come out of the calipers a bit. Without doing this its very hard to get the pistons out with special tools or damaging the calipers. Do this for both the front calipers.
- Once the pistons are pushed out on both calipers put a little put a hose clamp on the brake lines and remove the caliper. The clamp should stop any fluid leaking and will help when you reattach the calipers and rebleed the system.
- I believe the calipers are a MONOBLOCK) its one solid block of metal (sounds obvious I know). This makes things a little easier as bolts to hold 2 piece calipers together need to be high grade and tight! Remove the bleed nipples. It should be easy enough to buy need bleed nipples.
- Pull out each piston and make a note at which cylinder they go in (they will probably be different sizes). Each piston will have an outer and inner seal. The outer one will probably pop out with the piston, if not then prize out with a little screwdriver (they have small metal rings inside the rubber to keep their shape. The inner seals are simply shaped rings which fit snuggly into a little lip inside the cylinder.
- Make a note to show how the caliper is oriented, i.e. this way is the top and its the drivers side caliper. Photos will help. This is important as many calipers have different sized pistons and they need to go the right way around. For instance the coupe 20vt has the big piston at the bottom.
- Remove the join pipe from the bottom of the calipers. The chances are it will break or will be damaged when you remove it. You can probably buy new pipes BUT you can also make you own pipes. Similarly many competant garages will be able to knock up a new solid pipe in short time. They may not look standard but they will be just a good quality.
- I don't know for certain but many brakes have brake pad guides so the pistons don't get stuck. These are often stainless steel. Remove them if they are fitted and put them to one side.

Now take the calipers to a local powder coaters. You can get standard grade powder coating but there are some places that will do a nice textured finish (such as aerograde polymer coating) They should be able to sand blast the calipers (and they should also obviously cover up all holes and the cylinders so they don't get coated too). You could paint them yourself BUT painting stuff is a bit of a black art. Powder coaters can do they in hundreds of different colours but I'd stick to black for standard (or silvery for a plus)

Now you have a choice. Leave them purely black with no decals or get yourself some new RS decals (probably available from ebay). If you chose the later then have more choices - either get a bodyshop to put the decals on and spray over some high temp lacquer or have a go yourself. Again I'm inclined to leave it to the professionals.

Get them back the powder coaters and its a case of putting everything back together. BUT DO NOT RUSH IT!
- Even though they might looks really clean use an airline to remove any media from inside the calipers. You really don't want any grit in there.
- Clean all the pistons with brake cleaner so they are spotless.
- Apply some PTFE tape to the new lower brake join pipe too and screw those in nice and tight (did you remember which way was the top?)
- Now to the pistons. Push the inner seals into the cylinders and lubricate the seals with some red rubber grease (you often get this in kits but can be bought seperately). Some people lubricate the seals with brake fluid but I don't think this is as good.
- Push the outer seals (sometimes called dust seals) onto the tops of the pistons and ease the pistons into the cylinders. They should go in with a little resistance. Make sure you don't nip the corners of the inner seals, otherwise they will likely leak. Once the piston is all the way into the bore then apply some pressure to the outer seal and will fit into an outer sleeve in the caliper. It massively important that no grit is in there so double check.
- Before fitting the brake nipples, I'd suggest filling the calipers with brake fluid. This really does help when you bleed the brakes.
- Apply some PTFE tape to the new brake nipples and screw them.

And your done. Remember this is normally a job for professionals, so don't do it if your not 100% happy.

Then again you could just send them off to http://www.biggred.co.uk and they might refurbish them for you.

[ChrisRS6]

I've used BiggRed before (re-furbished a set of calipers on my 1970's Mk1 Ford Transit!!!).
I think the huge (2-pot) calipers cost around £140-ish to be re-furbed. I was very impressed with the service and quality of the finished calipers.

I think they stripped them right down (even to split the 2 halves), fitted new pistons, seals etc etc... and painted them in my choice of color and protection type.
Bit of an overkill I thnk, as the van has steel wheels and hub caps so you can't even see them, but I know they are there and look good!

Not sure how much they would charge for the monsters on the RS6 though...maybe not too much as the won't be as old and crusty as the 40yr old pair on my Van.

I know about the Brembos you are talking about Nobby. I've also got a 406 V6 coupe... and they can "squeal like a piggy" sometimes.