Flathead 6 smoking and blowby
I have started by 1940 Desoto for what Im guessing in over 10 years. The oil looked fresh and had good even compression readings. Oiled the cylinders and spun a few times before the first start. Car is not overheating but I do notice blowby through the filler neck white smoke from the exhaust.
What would be the best thing to begin testing or doing in order to eliminate this being that the car has sat for so long? Add a cleaner additive and change oil? add a ring sealer thereafter?
Some more info; I added a oil pressure guage and when cold it reads 40 psi once the car warms up it drops to 5-10 psi Is this huge decrease normal?
Any help is appreciated