I'm having a difficult time rebuilding a caliper because I can't get the stuck piston out. With significant PSI of compressed air and a worthy shield between me and the potential missile, it still won't budge. I've use PB Blaster and heat on it and still no luck.

Any ideas?

Thanks

Don

__________________
DAILY DRIVERS:
'84 300DT 298k (Aubrey's)
'99.5 Jetta TDI IV 251k (Julie's)
'97 Jetta TDI 127k (Amber's)
'97 Jetta TDI 186k (Matt's)
'96 Passat TDI 237k (Don's
'84 300D 211k Mint (Arne- Undergoing Greasecar Conversion)

SOLD:
'82 240D 229k (Matt's - Converted-300DT w/ 4 speed

The last rebuilt (MB) caliper I bought was $50 - might be time to just replace it.

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1984 300Sd 210k

Former cars:
1984 300D 445k (!!) (Strider) Original (and not rebuilt) engine and transmission. Currently running on V80 ( 80% vegetable oil, 20% petroleum products). Actually not, taking a WVO break.
1993 300d 2.5 275k. Current 120/day commuter
1981 300SD 188k (Hans) Killed by a deer

I have no problem buying rebuilds if that is the last resort but these things are very, very easy in theory. With five daily drivers, I wouldn't mind rebuilding them as it looks easier than most DIY jobs. The one piston popped out and the seals are so easy to replace. I took the rust off the opening of the one cavity and the piston slides in so nice now.

Thanks

Don

__________________
DAILY DRIVERS:
'84 300DT 298k (Aubrey's)
'99.5 Jetta TDI IV 251k (Julie's)
'97 Jetta TDI 127k (Amber's)
'97 Jetta TDI 186k (Matt's)
'96 Passat TDI 237k (Don's
'84 300D 211k Mint (Arne- Undergoing Greasecar Conversion)

SOLD:
'82 240D 229k (Matt's - Converted-300DT w/ 4 speed

The ones I've removed that were stuck would not have come out with compressed air.

I clamped down the other piston so it won't come out and then used the hydraulic force of the brake system to force the remaining piston out. You may have to pump the pedal hard a few times, but if it's going to break loose, it will.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

try tapping IN on it a bit first with something like the end of a wooden hammer handle, as it may be slightly cocked in the bore. Rap the outside casing sharply with a hammer all around too. Push out, in, etc. on the piston several times

If it won't come out with air and pb blaster then the bore will probly be too rusty and pitted for a rebuild. I have heard of using a grease gun on them but have never tried it..............

William Rogers...............

D-Don, A couple of suggestions;

One, Don't try to remove a caliper piston with compressed air. If it doesn't come at first people invariably stand in front of the piston, bend over and look straight in to it. A 2 in. dia. piston with 100psi air behind it has about 300 psi pushing it directly at your face. You probably don't have enough spare eyes and teeth to do this very often.

Two; You can, as suggested above, use a grease gun, esp. the ones with the long handle. They will generate about 10K psi. If that doesn't break it loose opt for a new calliper. Some where along the line your time and labor is worth something.