4 pot caliper seized piston
 

I bought a second hand set of 4 pots with a plan to refurb them with new pistons and seals however there is one piston on each caliper that won't move and it is almost right down to the bottom.

I don't have access to compressed air so does anyone have any idea how I can get the seized pistons out or if there is anywhere in the Glasgow area I can take them to get the pistons removed?

I know I could send them to Godspeed but I don't really won't to spend another 200 and odd quid on them.

Thanks in advance

I put mine in a vice, sprayed release agent on it and gripped it with a pipe wrench and just kept working it till it came out,you have to get a new piston anyway so it doesn't matter if you damage the piston

The way to do them. Although pain in the a**e in this case, is to connect them to the braking system. Clamp the good piston and pump the pedal to force the seized piston out.

Try west of Scotland engineering there down off the Clyde express way somewhere I know they do brake calipers as they did my mates brembo a for him

I did think of that but it will be a pain in the ass!

I've been spaying with wd40 and trying with a pipe wrench! Looks like I'll have to get someone with a vice!

Agree with turbobits, but could be worth spraying into caliper with WD40 for a few days to try nd loosen things up a bit.

Try a good penetrating oil instead ,like plus gas ,as it works better

You can use a grease gun, it means you will have to clean them repeatedly when done. you'll also have to improvise with clamps etc to stop the other 3 pistons. Using a pipe wrench will mark/scratch the surface of the piston.

Thanks for that. It's only one on each caliper which is a pain!!

I had a look at the grease gun method on YouTube but looks very messy!!

I'm going to order s/s pistons so not too bothered if I mark the one that's seized as long as I get it out.

Where's the best place to get plus gas?

In which case pipe wrench and twist as you pull.

Would a petrol station air machine do it if you put a really high psi?

No, and I'd imagine the petrol station would also get the hump as they come under some force and make a "pop".

Lol if it would of worked I would go later at night. Lol

As above clamp them and just pump the bad one/s out.:thumb:

Get some freeze and release from Loctite around £5

a few years ago i had the same issue and got my old man to tap the inside of the piston and then got a fecking big bolt and screwed that in, then bolt in vice and tap the calliper off.

i then just cleaned up the piston as it was ok, just seized in the seal and i was fitting new seals etc anyway.

saves destroying the pistons!

I've used wd40 and a silicon lubricant but still no movement. I'll try the freeze and release tomorrow if I can get it locally.

Thanks

another option is leave them in a bucket of diesel, as that can penetrate.

have you stripped the callipers down at all?

if not, then it may be a good idea so you can get some lube in there

Yes, I've got the dust seals off all the pistons just not took the other pistons out yet.

The easiest way to get the pistons out is hydraulically with the brake pedal , you have to clamp the free moving pistons so the pressure is going to the stuck one , the next best way is compressed air , but sometimes even 150psi is not enough.

I have made up a hydraulic pump on the work bench to remove stuck pistons , we never fail to get them out with this.

If you have no access to either of the above , it will be brute force and ignorance that gets them out , along with blood sweat tears and plenty of swearing lol.

Thats why most send them to us in exchange for nice new shiny ones :D

Cheers Ian

Thanks Ian,

I would have sent my original ones but as per my pm the other week, I have one caliper with the imbosed sign and the other is the newer style with the sticker sign( previous owner mod!!!)

I purchased a set from eBay for £100 (sticker style) and am going to order your refurb set....If I can get the stuck ones out!!

Just a quick update.

I finally got the pistons out by biting the bullet and connecting them upto the car. They are now finished:)

http://s1321.photobucket.com/user/si...tml?sort=3&o=0

They look awesome mate was it easy rebuilding the pistons?

Nice one mate.

5cooby1, they are pretty simple to do if your handy with the spanners.

Yes, as said they are pretty easy. It only took about 10 minutes to put the new seals and pistons in. The hard part was getting the seized ones out!!

Oh and thanks, I'm very happy with them!!

Thanks above will look into this for mine I think

I just took one wheel off and done both at that side.