YACT: Changing brakes on a car with ABS. Edit: Need a bit more help...

[CrackRabbit]

I was going to change the brakes on my G20 today when I realised that the car has ABS. This is the first car that I have worked on the brakes that has had ABS, normaly to get the caliper piston back into the caliper I use a C-clamp and a block of wood to force it back in.
Will this method still work or can it damage the ABS system?

Thanks,

CrackRabbit

Well I tried to get the job done today, started with the rear first since they were the most worn and starting to squeak. but i ran into a slight problem, I couldn't find a way to force the piston back into the bore and ended up breaking my c-clamp in the process. Is there any other way to force the piston back, should I get another c-clamp or just give up and take it and get it done at a shop?

 

[Demon-Xanth]

Never noticed anything different other than the presence of a sensor that you need to make sure you don't break off (requires some serious fucknuttery) when we did the brakes on my Dad's Ram.

 

[virtueixi]

You may have to bleed the brakes.

 

[DougK62]

I've always used the exact method you described on my ABS cars with no troubles.

 

[halik]

Originally posted by: CrackRabbit
I was going to change the brakes on my G20 today when I realised that the car has ABS. This is the first car that I have worked on the brakes that has had ABS, normaly to get the caliper piston back into the caliper I use a C-clamp and a block of wood to force it back in.
Will this method still work or can it damage the ABS system?

Thanks,

CrackRabbit

the only thing you need to worry about is the abs sensor. Just make sure it doesn't get damaged in the process. You can compress the piston back no problem.

<- broke his ABS sensor on accident... damn german engineering, you'd think the stop-notch on the sensor would put just deep enough to not come in contact with the CV join. Not so much...

 

[CrackRabbit]

Thanks Guys! I am off to fix my car!

 

[CrackRabbit]

Update, and need a bit more help...

 

[Quixfire]

Rear calipers pistons have to be turn into the caliper to compress them. They don't just press in because the parking brake mechanism is built into the caliper. Most of the time you need a special tool to turn the caliper piston so I would check you local part store to see if they sell one for your car.

 

[Minjin]

Always crack open the bleed screw first. Then, when you force the piston back in, the excess brake fluid will be purged via a vacuum tube you put over the bleed screw into a container to be disposed of. If you don't crack the bleed open, you are forcing all the fluid back through your system and in the case, of cars with ABS, through the ABS pump. This isn't good.

As mentioned above, rear calipers that are used as a parking brake will generally require the pistons to be screwed back in.

Mark

 

[shadduphoe]

hwat year g20? i have one too.. 94..

 

[CrackRabbit]

Originally posted by: Quixfire
Rear calipers pistons have to be turn into the caliper to compress them. They don't just press in because the parking brake mechanism is built into the caliper. Most of the time you need a special tool to turn the caliper piston so I would check you local part store to see if they sell one for your car.

Ahhh, had no clue about that, I have never had a car with rear disc brakes before I will have to check at the parts store tomorrow.
Its a 91 G20, I like the car alot, just needs a little work to make it perfect.

 

[Minjin]

If you squeezed the rear piston so much that you BROKE a c-clamp, you: A. shouldn't be working on cars....and B. better hope you didn't damage the caliper. As I've said before, working on your own brakes when you don't know what you're doing can possibly kill you and innocent others. Please think twice next time.

Mark

 

[CrackRabbit]

Originally posted by: Minjin
If you squeezed the rear piston so much that you BROKE a c-clamp, you: A. shouldn't be working on cars....and B. better hope you didn't damage the caliper. As I've said before, working on your own brakes when you don't know what you're doing can possibly kill you and innocent others. Please think twice next time.

Mark

Thanks for the insult, I have been working on my own cars for several years now and have done the brakes on several models. Just never one with rear disc brakes before. The c-clamp was a cheapy chinese job anyways.
If you have nothing nice or constructive to say get the hell out of my thread and please think twice next time before posting in another one.

 

[tfinch2]

Chilton/Haynes manual FTW!

 

[Ronstang]

Originally posted by: Quixfire
Rear calipers pistons have to be turn into the caliper to compress them. They don't just press in because the parking brake mechanism is built into the caliper. Most of the time you need a special tool to turn the caliper piston so I would check you local part store to see if they sell one for your car.

Ding Ding Ding!!!!! We have a winner. But then again he is a professional mechanic. take his advice. Borrow the right tool. The cheapie ones you can buy that go on a socket wrench are a joke and an accident waiting to happen.

 

[CrackRabbit]

Alrighty I think I found what I need on the Autozone website, it is listed as a "caliper spreader". That is the thingy I need right? I just want to make sure before I go there tomorrow and get it and find its not what I needl.

 

[Wingznut]

Originally posted by: CrackRabbit
Alrighty I think I found what I need on the Autozone website, it is listed as a "caliper spreader". That is the thingy I need right? I just want to make sure before I go there tomorrow and get it and find its not what I needl.

That could be it... Make sure it screws the piston in, and not just compresses it.

You could try using a pair of needle nose pliers... Just insert the tips into the holes and screw the piston in. Sometimes, it's too tough to do, and you'll need the special tool. But many times, the plier trick works just fine.

 

[cmv]

Your c-clamp may have broke because the pistons on your rear calipers have the parking brake system integrated and the pistons rotate as they go in and out. If so, you can go borrow a tool at Autozone for $35-$40 on your credit card (refunded when you return it) to push in the calipers. It's still a little tricky -- the rears on my 99 Jetta GLS are like this and the first side took 30 minutes but the next side took less than 5 (to push in the rotating piston).