Caliper piston persuader

[john walker's workshop]

Thought that I better get busy and process my pile of stuck calipers, especially two SC rears i want to use on my '69 project, which will save me about $400 over buying new ones. I ordered this bug master cylinder and metal reservoir from CIP1 and whipped up this quickie setup to push out the frozen pistons. Works great. Shoulda made one years ago instead of fighting the damn things.

[RWebb]

'69 project ???

is there a thread yet?

[Ok here we go]

Damn, should've brought my 3.2 calipers to you, John. Spent the better part of a weekend trying to get the frozen pistons unstuck from the 3 out of the 4 calipers.

[john walker's workshop]

There are times when air pressure doesn't get it. Most times lately.

[911tracker85]

I read somewhere using a grease gun also works well. is that correct? getting adapters may be a challenge?

[Dr J]

Great idea. Pressurized hydraulic fluid for this purpose is much safer than compressed air.

[sf911]

Originally Posted by 911tracker85

I read somewhere using a grease gun also works well. is that correct? getting adapters may be a challenge?

I've used a grease gun for years . Just remove the bleeder and screw in a Grease Zerk [ nipple ] . I guess the only problem is grease in the caliper but you are taking it apart anyways .

[john walker's workshop]

I think a different handle is in order. A downward pusher would be easier than pulling. An L shape. Some of these things were really stuck, but they moved a 1/4" with every pump. Don't see how a grease gun would have moved them.

[jlex]

Clever gadget. I used compressed air on mine, but you've got to be really careful to keep your fingers out of the way.

[sf911]

Originally Posted by john walker's workshop

I think a different handle is in order. A downward pusher would be easier than pulling. An L shape. Some of these things were really stuck, but they moved a 1/4" with every pump. Don't see how a grease gun would have moved them.

You're right John , I had one of my 69 ,many years ago , that was so corroded that by the time I got the piston out with a grease gun and a lot of heat ! I had to get the caliper bore sleaved and a new piston . Your rig looks very cool !

[john walker's workshop]

That was just a rough quickie design to see how well it worked. I cleaned it up a bit today and made a long round, push down handle instead of the flat pull handle. Much more comfortable.

[Will 1967]

That setup will leave lot less cleaning but grease gun without tip wil screw right to caliper, and that will drive any piston out regardless how stuck they are. So works very well if doing calipers occasionally, but your setup is quicker as its slow to clean grease from everywhere. I'm literally just now putting together 14 calipers (yellow zinc plated and all rebuild) and I needed grease gun for every single of them.

[911tracker85]

I used compressed air on mine, but you've got to be really careful to keep your fingers out of the way.

yep. I quickly learned to cover the caliper with a towel to catch the piston and keep anything from flying off.

[Bill Douglas]

Originally Posted by 911tracker85

yep. I quickly learned to cover the caliper with a towel to catch the piston and keep anything from flying off.

Good thinking. I wish I'd done this a while ago. I had a spare pair of calipers lying around so I thought I'd free up the piston by compressing it with a g-clamp. Wooo, it suddenly freed up. Fluid shot out the brake line hole, clipped the side of my head and splattered onto the ceiling of the renovation house I was using as a workshop LOL It stank for a week

[john walker's workshop]

Modified the thing a bit.

[Discseven]

Nice one John!

[Bill Douglas]

Looking good around there John. How is the new location working out?

[NYNick]

Recently took 2 hours getting 4 frozen pistons out of the rear calipers on my 72. We C- clamped them back a little, applied air, got them to move a little, repeated the process etc over and over with liberal applications of PB Blaster. Those babies were IN THERE, but they finally came out with a loud POP!

I damaged one of the pistons beforehand by man handling it with some vice grips. I received a new piston today, but it does not have the cir-clip and tube set up inside of it.

How does one remove the old piston inside parts and reinstall them in the new one?

[john walker's workshop]

Originally Posted by Bill Douglas

Looking good around there John. How is the new location working out?

Been staying pretty busy up here. Lots of my old customers don't seem to mind the trek. Don't miss the Seattle shop too much ($$$), or the year I spent commuting until I was out of there. Pretty quiet up here in the trees.

[RWebb]

pretty - but I bet you are not as close to a bewpub as you were...