i got this project truck (1986 chevy s-10 body droped with air bags)and i put a 350 small block in it engine ran good last time i had it running that was last summer, today i started it ran for about 4 minutes and it seazed it had lots of oil pressure water was still cold

so i took all the spark plugs out then it would barely turn over so i sprayed WD-40 in it and it hepled but its still a little heavy

what could of caused this??

thanks in advance

if you could some how take a bore scope and look into the cylinders you will most likely see some corrosion of some sorts. Years ago I stored a Pontiac GTO and some how I accumilated a lot of moisture in the cylinders wall and rust formation occured. The mech told me it was caused by the headers and glass packs and how humid it had been all summer. I removed the heads and cleaned out the cylinder walls and removed everything I could and put it back together. It started just fine but was never the same. I traded it a few months later. Sure wished I kept it. It would be worth a mint right now.

ohh ok yea that might be it but its been sitting in out floor heated show all year it didnt have a carb on it but i duct taped the intake manifold so nothing would get in it i didnt really want to take the heads off sinse id have to replace the gaskets and the engine is a brand new rebuild thats bored out with after market pistons and cam and all that good stuff but i guess ill just have to order a new pair then lol

put a bore scope when you remove a spark plug, inspect the cylinder walls and see if you can detect any issues within, you may want to see if there is any scaring, maybe a ring became unseated, almost unheard of, but if engine was built out of tolerance you may some other issues