Pitted caliper piston- can i use it?
 

http://forums.pelicanparts.com/uploa...1333124934.jpg

I am rebuilding my front calipers and ran across this pitting on one of the pistons. Will I have a problem using this?

Thanks!

I would get a new one. The pitting can make it leak and/or damage the seal.

Kay

That is beyond pitting ... much safer to get a new one !

Cheers !
Phil

I agree that the best answer is to get a new one.

This corroded area was probably outside of the inner seal (the square-cut O-ring) in the caliper cylinder, and was therefore exposed to the elements, probably due to a failed dust boot. While it's possible that you could polish this area down, unless you could get it perfectly smooth without altering the dimensions of the piston, it may damage that O-ring, or allow fluid to leak if depressed all the way into the cylinder, such as when new pads are being inserted.

There's no real up-side to re-using this, and you might think about replacing the whole caliper.

the only pistons I've seen available are for earlier years? I have a '79. recommendations on where I can find some?

They are available from Eric Shea (pmbperformance.com)

+1 Eric does AMAZING WORK on brakes.

Also... when it comes to brakes, no matter what I will not skimp. When in question about the very thing that keeps your life safe every time you press that pedal, it's best to make sure it's rebuilt properly or new.

Thanks for all the advise everyone. Those were my thoughts but just wanted to make sure before I shelled out another $70+ per caliper for new pistons. I will probably eventually upgrade to big brakes and didn't want to spend unnecessary money getting these up to par for the time being.

That is not pitted... it is dead.

I would measure how deep the seal is in the bore and see if that area will touch the seal. If not then it would be ok to use (especially for a short time).

-Andy

Ask yourself this question....when driving down the road...and a big truck carrying gasoline pulls out in front of you and you have to make an emergency stop....will you make it with that piston?
Or...for the sake of a few dollars...?
Bob

Everyone makes very valid points. Thanks guys. With that being said.. new pistons it is! That is as long as my inspection of the calipers don't show any pitting as well..

I would not use that personally on my car.

Wayne

My thoughts exactly...I doubt the pitted area is anywhere near the business portion of the piston. What would affect this is the brake pad thickness. The further the pad wears, the more the piston extends out from the seal.
However, if it were mine, i'd replace it

If the seal isn't touching it, which I doubt, it's just as good as a new.

OUT, it goes. Sooner, the better.

Best!

Doyle

Using that is a good way to meet your local ambulance crew.