Literally Stuck: Rebuilding a Vintage Girling Brake Caliper - Pic

[slow&rusty]

Hey Guys - I am rebuilding the rear Girling caliper (1972 vintage). The piston is completely frozen in the bore.

I tried using the piston removal slide hammer tool (seen in the picture) with heat and zero luck.

Any suggestions??



Thanks,
Yasin

[A930Rocket]

Soak it in PB Blaster and use air to blow the piston out?

Do you want to salvage the piston? I was thinking maybe use heat and PB Blaster with a pipe wrench or similar to break it free.

Is it square in the bore?

[DRONE]

The machinists in me says to put it on a mill and bore it out of course no more piston but a reusable caliper

[ltusler]

I've heard about pumping grease in but have'nt tried it.

[Shaun @ Tru6]

^^^ I used a grease gun once, it worked but was extremely slow. And very messy. Someday I'll build a proper hydraulic system with a brake pedal to push pistons out easily. Been very lucky with air on Turbo calipers.

[A930Rocket]

Any chance you can press it in to break the bond?

What about an ultrasound cleaner?

[TimT]

Use a vice or c-clamp and see if you can move the piston in, you'll know if it is moveable or totally frozen... If you can move it, use a grease gun, or hook it up to a brake system and use the brake pedal to force the piston out..

[sc_rufctr]

Originally Posted by A930Rocket

Any chance you can press it in to break the bond?

What about an ultrasound cleaner?

Originally Posted by TimT

Use a vice or c-clamp and see if you can move the piston in, you'll know if it is moveable or totally frozen... If you can move it, use a grease gun, or hook it up to a brake system and use the brake pedal to force the piston out..

This and this. You have to get that piston moving.

(Obvious but...To use grease or air pressure you'd have to reassemble two halves)

[pwd72s]

A puller...to "pull" the caliper (held in a vise) through the piston? Actually then pushing with the puller screw? Good soaking with PB blaster first...

[unclebilly]

What penetrants have you tried?

You need to hit it with pressure. I hope the heat you have applied hasn’t damaged the aluminum.

[GeorgeK]

Soak in salted vinegar a few days?

[Arizona_928]

Originally Posted by ltusler

I've heard about pumping grease in but have'nt tried it.

I’ve done it and it’s a messy process but it works.

[Steve F]

I used a hand held hydraulic pump used for various jaws of life tools, 10000 psi , worked great , just walked it out.

[slow&rusty]

Thanks guys.

I soaked it again last night with generous amounts of PB Blaster and then put a pair of vice grips on the piston and worked it back and forth and finally walked it out. The vice grips of course marred the piston, which is OK as I have a new piston and re-build kit.

I appreciate the help!
Yasin