Brake Caliper Rebuild

[swedishandgerman]

If anyone is mad enough to rebuild your own front brake calipers instead of spending the £97 on a reconditioned one, here's how:

This is quite something: on a 3 pot caliper, the inside piston seizes up with age. Even so, they still seem to give sufficient pressure to pass an MOT even on the 2 little pistons. So even if you think your brakes are in tip-top, it's still worth checking things out

My old car had been standing for a few months, so when it went in for its MOT recently, it failed on brakes binding. I thought about levering things, but on closer inspection, the rubber components were brittle and the pistons were exposed looking very rusty

After taking the wheel off, I took the pads out. This is so simple - there are 2 guide pins held in with little locking clips. Once removed the pads can be lifted out, measured, inspected and cleaned up.

Taking the calipers off involves undoing 2 bolts that include a locking tab. Also disconnecting the brake pipe. I soaked these overnight in oil and I was lucky that they came off with little effort and didn't distort the pipe. Don't over force your spanner on these as they easy shear.



Next, you need to extract the old pistons. Apparently, you should use an airline, but I don't have one and seeing as these pistons were scrap, I put the whole caliper in a vice and levered them out with a grip. They were tight, but came out eventually.

Nasty looking! The corrosion build up is what makes the pistons jam up. Normally, they should float in and out on the rubber and not come into contact with the caliper body.



All the old rubber needs to come out.



I am lucky; I work for a shot blast manufacturer, so my calipers extraordinarily found their way into one of my customer's machines.



After, I sprayed them in a high temp silver paint.



A complete recon kit is available form Brookhouse including 3 pistons, 2 dust covers, 3 seals and a new bleed screw

Fitting in the seals was easy. Fitting the dust covers was fiddly. Putting in the pistons was more than fiddly.

1. Put the seals into the grooves,
2. Put the dust covers into position making sure they enter the grooves in the cylinders
3. Stretch the dust covers and with your imaginary second pair of hands - if you're lucky enough to have some - put the pistons into the cylinders, make sure the dust covers enter the piston grooves and fully inset them. This is a frustrating little job!

Now it's ready to go on the car making sure you remember the safety tab behind the 2 bolts. Reconnect the pipe, re-insert the pads, pins and locking clips.

Bleed the system and surprise yourself by how bad the brakes were before!