Remove pistons while engine is in the truck?

[njjeeper]

Is it possible to pull the pistons with the engine still in the truck? Can they come out the top if there is no wear ridge? I have some badly stuck rings and Im not sure running it is going to free them. The truck runs really nice and starts easily. But I have about 50 psi in the 2 middle cylinders and smoke with it ice cold. I figure if I can pull those pistons and work the rings free I may be able to at least make this motor a parade cruiser.

[Kaegi]

yes they come out the top. inframe rebuilds were common back in the day.

[RMS]

if i remember correctly the pistons will only come out the top. i believe the mains are in the way for bottom extraction. do you suspect the rings to be rusty or gummed up ? if you don't suspect rust has seized the rings i would try some ATF. ATF works great for removing rusty bolts (works better than most penetrating lubes). ATF is high in detergents and cleans better than mineral spirits. clean a cylinder bore with mineral spirits till the rag comes back clean, then hit it with some ATF you will be surprised at how dirty the rag becomes. the strange thing is used ATF works better at freeing bolts than clean ATF if it is water damage and your pistons are fuzzy with oxidization tear the motor down and do a complete rebuild. a strong running truck is a lot more fun than one that has to be limped around. well unless you enjoy the uncertainty of not making it home

[Wayne64]

I totally agree with trying ATF, freed up a 1961 seized outboard that way and it ran great after a 3 month soaking. As an aside when building an engine it was always common practice to lube up the cylinder and piston with engine oil. It is much better to use ATF for piston installation as ATF will not gum up the rings when it gets hot.