Might want to check for stuck valves, other wise bent pushrods can happen. If the head is pulled, a lot can be figured out. If the solvent method does not free the rings, etc., Coke or molasses in each cyl. Does the job, takes some time, though. If there is any water in there now, get it out w/ air and or alcohol. Also make sure pan has no water in it like has been said above.

'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.