Head Gasket?

[1980]

Hey Guys, New here & glad to be a part of this bunch.
Question: 1980 350 no emissions.
Thermostat stuck & ran hot for 3 days, did not boil over.
Installed new thermostat & ran fine for 2 days, then on the hiway at 60 mph, lost power blowing pure white smoke and stalled. towed home, now will start at full pedal, barely idle, still blowing white smoke.
Head gasket\cracked head\block? How do I test?
Thanks for any help.

 

[Cowboy_80]

Not sure how you managed to keep it from blowing over, but cool. I'm not going to guess what is wrong, whether it be a gasket or cracked iron. You have to pull the head off either way. Hopefully it's a gasket and all you need is to replace it. Might as well do both sides. Can be done in <4 hrs, but if you haven't done it before, plan on it being a weekend project. If it is a head gasket, you will be able to visually tell. If you can't see anything wrong with the gasket, it just might be a crack. Bring the head(s) to a machine shop and have them check. If the heads come back okay, the bet I can say is to replace the gaskets, put the heads back on and see if the problem went away. If it didn't then the block is done. Replace your oil as well since water is probably in the crank case.

 

[vortec]

you could have warped or cracked the block or heads and the water was discharging into the engine or leaking past the plugs in the block instead of boiling over in the expected way. first thing i'd do is drain the oil. if it looks normal, that's a good thing. if it's a milkshake, get ready for some "fun". BUT, normal oil does not mean your head gaskets, block and heads are fine. it just means you have less cleanup ahead. you'll still have detective work to do.

 

[1980]

I live 20 miles from town, so what I need to know is how can I analyze the problem, say compression test or something, or do I have to drag this truck to town? Thanks

 

[1980]

Gonna bump this up.
Will a compression test tell or indicate anything about this problem?

 

[broke73]

A compression test is going to tell you that you have a bad head gasket, warped or cracked head. It'll let you know which head but not what the problem is. Blowing white smoke indicates the above.

 

[SoCal'75]

pull the spark plugs and look for the one/ones that are "clean" or show signs of rust. That will give you a starting point for finding the problem. You may not have to pull the whole thing apart.Good luck
-Lance