*HOW TO* Refurbish brake calipers / 308mm brakes on a Meriva/ Corsa C

This How to shows you how to refurbish a set of ATE Calipers

I had a set of 308mm calipers that needed refurbishing from a Astra Coupe Turbo, however this "how to" can be applied to any of the ATE calipers that Vauxhall have employed on their various models.

IMPORTANT - If you are not a competent mechanic comfortable dealing with the braking system of a vehicle then hand this job over to some one else who is. Brakes are a critical component of a vehicle and if the correct procedures are not followed then serious or fatal injury could occur to both you and other road users.

Right first off - I started with a set of cruddy 308mm Astra G calipers. Fortunately the calipers had brand new pads and the vehicle had brand new discs so it was just the condition of the calipers that concerned me.

http://i2.photobucket.com/albums/y15.../Brakes001.jpg

http://i2.photobucket.com/albums/y15.../Brakes002.jpg

So I stripped down the calipers to the various components and gave them a wish with a flapper disc in my grinder, and also a going over with a wire wheel attachment in my drill . I then soaked them in my tub of vinegar for a few days to clean them up a bit and this was the results :-

http://i2.photobucket.com/albums/y15.../Brakes003.jpg

http://i2.photobucket.com/albums/y15.../Brakes004.jpg

http://i2.photobucket.com/albums/y15.../Brakes005.jpg

If you have access to media blasting equipment (I don't) then you may get even better results!

I then used some silver smooth Hammerite and gave the components a couple of even coats. You could use brake lacquer , spray them, or even have then powder coated. Just make sure you do not get any paint into where the piston sits as this will make it bind and binding brakes are not good!

http://i2.photobucket.com/albums/y15.../Brakes008.jpg

http://i2.photobucket.com/albums/y15.../Brakes007.jpg

http://i2.photobucket.com/albums/y15.../Brakes006.jpg

I then purchased a rebuild kit of Ebay for about £22 which I thought was good value - the parts from Vauxhall are about four times this !

http://i2.photobucket.com/albums/y15.../Brakes009.jpg

http://i2.photobucket.com/albums/y15.../Brakes010.jpg

I then set about rebuilding the calipers. The slider bolts live in two rubber housing at each side of the piston, these just need pressing through. There is a rubber seal within the piston housing about 1/4 from the top, this needs replacing and then the piston dust seal needs putting on.

I found that is was easiest to put the seal about 1/4 from the bottom of the piston, then slide the piston (with a little oil or brake fluid as lubricant) into the cylinder about 1/3 of the way in. Then make sure the lower rubber lip of the dust seal sits in the recess around the cylinder. Finally, push the cylinder all the way down and the top edge of the seal should move up and pop into the top groove. Job sorted. Its a bit fiddly and took a couple of attempts to get right.



http://i2.photobucket.com/albums/y15.../Brakes011.jpg

http://i2.photobucket.com/albums/y15.../Brakes012.jpg

When fitting callipers make sure the bleed nipple is at the top of the calliper otherwise you will always have air in the system and a spongy pedal. It's easily done, and I have done it in the past and couldn't work out why I had a rubbish brake pedal !

Next job is jack the car up and put the axle stands underneath for safety.

http://i2.photobucket.com/albums/y15...a/IMG_8798.jpg

And start removing the standard 280mm brake cailpers and discs ...

http://i2.photobucket.com/albums/y15...a/IMG_8799.jpg

First job is to clamp the brake hose so you do not lose all the brake fluid out ...

http://i2.photobucket.com/albums/y15...a/IMG_8804.jpg

Then crack the banjo bolt that holds the brake pipe to the caliper and remove. There will be a small amount of fluid loss from the hose and caliper so put a rag or cloth underneath before you undo the banjo bolt.

Continued below ..

Then undo the two retaining bolts with a E18 torx socket...

http://i2.photobucket.com/albums/y15...a/IMG_8803.jpg


And remove the calliper. The disc can now be removed, if it has one fitted remove the bolt with an allen key/allen key socket . The disc in theory should now be removed, however if it is rusted on, then some gentle persuasion with a hammer may be required !

Once off you should be left with something like this …

http://i2.photobucket.com/albums/y15...a/IMG_8805.jpg

This flange is only 2 years old and is already rusty. Vauxhall do not coat these with anything from the factory so the discs tend to rust to the flanges and become solid.

I cleaned mine up and put a thin coat of copper grease on the face to eliminate future problems should I need to remove the disc in the future …

http://i2.photobucket.com/albums/y15...a/IMG_8806.jpg

Next up is put the new 308mm disc on and bolt up the centre bolt with an allen key again. Then put the calliper carrier in place. At this point I found that the Astra G calliper carriers are the wrong shape and will not fit up against the hub. The solution for a corsa C / Meriva hub is a set of calliper carriers off a Meriva VXR which I sourced new for £48 each . Use thread lock with the bolts….

http://i2.photobucket.com/albums/y15...a/IMG_8908.jpg

The put the pads in , using a thin layer of copper grease on the backs of the pads to stop brake squeal …

http://i2.photobucket.com/albums/y15...a/IMG_8909.jpg

And then put the calliper onto the carrier and tighten up the slider bolts onto the carrier ….

http://i2.photobucket.com/albums/y15...a/IMG_8910.jpg

Reattach the brake hose , if the hose is old you may wish to consider replacing the two copper washers (one on each side of the hose fitting) and bleed the brakes with either a pressure bleed system , or an assistant pumping the pedal.

http://i2.photobucket.com/albums/y15...a/IMG_8912.jpg

Now go and do the same on the other side of the vehicle .

Put the wheels back on, remove axle stands, drop to floor. BEFORE driving off pump the pedal a few times to move the piston out to the correct position. Go for a drive and check the braking. Double check the callipers for any signs of leaks .

Let the pads bed in for a couple of hundred miles before spirited use!

And here is proof 308mm discs fit under 16” Vauxhall alloys ….

http://i2.photobucket.com/albums/y15...a/IMG_8914.jpg


Joff