How to open the brake's bleeder?

[SEREGA784]

How to open the bleeder when compressing the caliper piston? Where is it located? Picture would help. I have 99 Grand AM.

[SEREGA784]

And do i really have to do that for all cars? (I change brakes for other car as well)

[xeroinfinity]

10 mm wrench, it is on the back of the caliper.
should have a rubber boot thing covering it, maybe not.

Just start compressing the piston lightly then open the bleeder slowly to allow the fluid/pressure to escape.

If you dont do this all you do is push all that old moisture ridden fluid backwards through the system, and it can and will make breaking less effective.
It can also damage the ABS modulator, and thats not something you want to replace(its under the battery), a real pita plus pricey, if you ask me.

Read this if you have time and you might under stand breaks a little better.
Brakes 101 ...

good luck

[inafogg]

hello serega im new to site not sure if question is current any way u do not need to open bleeder on calipers.if u are just replacing brake pads push piston back in using clamp or big set of pliers.depending on fluid level u may over fill master cyl. but no big deal. hope this helps Mike

[xeroinfinity]

Welcome to AF inafogg.

You can not just push the piston in !!!!
Maybe on some pos 1970's -1980's automobile you could get away with that, but still - problems will arrise.

Three good reasons why NOT to shove the pixton in..
1- pushes the old fluid which contains small particals backwards through the hydralic sytem thus making braking poor.
2- it pushes moisture that is in the lines back up into the system causing more spongy brakes.
3- This also can and will damage the ABS modulator and other components in the braking system.

Please read the Brakes 101 from post #3

IMO if this wasn't a problem,
then thier would not have been 1000 people in the last year posting about spongy brakes, and the right rear wheel locking up and dragging.

PS- also watch out for pushing the piston down to hard as this can bust the bottom right out of the calipers piston then you'd need to replace/rebuild the caliper = more $$$.

[inafogg]

hello i dont want to get in a disagreement with some people. u replaced brakes on other cars did u open bleeders on them? i dought it. i been a tech for 37 yrs sorry but never heard of or had a piston blow out give me a break, or spongy breaks or lock up if u want to bleed ok but just be careful not to break bleeder good luck Mike

[xeroinfinity]

Appearently we are at a disagreement, but that's alright.
You do things the way you have done them, and I'll do them my way(the right way).

It is uncommon for the caliper piston to bust, but it does happen more then you'd think. Sorry you havnt witnessed this little issue for your self.