Packard Forum Index » V-8 (1955-56)

I have a 1956 Executive with a stuck engine. Car was driven into storage many years ago and left. Had oil in engine & anti-freeze. I tried different penetrants in the cylinders with no luck. I can move the ring gear slightly- maybe 1/8-1/4" max, but no movement on pistons. I now have heads removed and have been soaking piston tops with PB blaster and hitting them with hammer on wooden block. Article on you tube claims wood will not transfer jolt to the pistons- it says to use a metal pipe. I have been doing that but no luck. Don't want to hit too hard in case of breaking a piston. Inside of engine [cylinder walls] look to be in great condition, but no movement in pistons. Anyone have any suggestions that I may try? Thanks.

I have a similar issue on mine. Unfortunately no solution so far.

I would not hit metal with metal. The pistons are aluminum and will be easily damaged. At least use a thin spacer of wood or plastic between the rod and piston.

One thing I've heard people do is pour rust remover like Evapo-Rust into the cylinders to try to break up any rust that exists between the walls and rings. However I'm not speaking from personal experience so I'd wait for some other opinions on here before trying it.

Trying to save the pistons is 99% a waste of effort. If there is enough corrosion/rust to stick the pistons, it's a sure thing the cylinders will be so pitted they will have to be bored to clean up the pits.

jack vines

The last time I had a stuck V8, it was the wrist pins that were frozen. It wasn’t a Packard engine (Imperial 413) but still, pistons aren’t the only thing to stick!

Drop the pan and remove the crankshaft. If it is on an engine stand, turn upside down and soak pistons with penetrating oil from the bottom. You can then use wood block on connecting rod to tap pistons out of the block.

Kind of along the lines of what John said,
drop the pan and loosen the rod bolts then see if pistons will move. You may find only a couple that are stuck and you can concentrate on them. I had only one stuck in my 12, once it was loose the engine turned over easily.

Thanks to all who answered. I was thinking of removing the pan- engine is in the car so not much fun, but it looks like that's my only option.

Can't imagine a good outcome of trying to do what you're doing with the short block still in the engine compartment.

What may have seemed like an easier way will from experience turn out to be the hard way.

jack vines, who's learned most everything the hard way.

I have an update with my car here:
packardinfo.com/xoops/html/modules/newbb ... 4406&post_id=243509#forumpost243509

I recommend setting a torque wrench to 150 ft-lbs and using that to turn the crank bolt. That way you won't damage it by accident. Start clockwise and tighten until the torque wrench clicks. Then use a normal ratchet or breaker bar to turn it the opposite direction until the bolt unscrews (or use the torque wrench, but some torque wrenches are damaged when unscrewing so double-check that that's okay on yours).

That's what I did on mine, it didn't budge when turning it CW but I was able to turn it CCW without much trouble. It turns 1/6 of a turn back and forth now. Remains to be seen how I'll get it to turn the remaining 5/6.