Trying to troubleshoot a motor that has been sitting for 3 years. was on a roll over. It's a 97 4.0 with only 66K on it and the previous owner said it died right away when it went on its lid. They never tried to start it after that and just let it sit for 3 years. I got it running pretty easy, changed the oil, and after the first initial smoke of it burning oil that had leaked up into the manifold, it will now start to puff slight white smoke (not clouds of it) after engine is at normal temp and running/idling for about 10-15min. If it isn't doing it I can get it to start by reving up to about 3K several times. It doesn't look like blueish smoke more white, but that all goes out the window once you stare at anything long enough. My sniffer isn't that good and I can't tell if it smells like coolant or not. There is some drip at the tailpipe but not much at all.

This is what I have done so far.
-diluted 3 year old gas about 1/4 tank with 11 gallons of good stuff and used injector cleaner
- pulled plugs, they all look good with no ash deposites or crystals on them, they look really normal. #4 and 6 were in appearance a little cleaner, but not much.
- Ran compression, lowest was 137 highest was 145 (I live a 5000ft)
- Re-torqued the lower intake
- Ran a combustion leak test in the radiator, no leak detected.

Could it be the bad gas still or water in the fuel system? I would think it would do it from the get go if it was.

I want it to work out because I have a 2000 that needs a motor, but, I don't want to drop a turd in it. Should I just go for it and see if it clears up with all the other stuff from the newer truck that hasn't been sitting so long? My gut kind of tells me it might still be the intake gasket, I could do that pretty easy when the motor is out, but I don't want to throw parts($) at it anymore than I have to.

Any other ideas?
Thanks.

 

What engine are we talking about? 4-banger? 3.0L? 4.0L?

 

Sorry, I edited it up top too. Its a 97 4.0.

 

It's a tough call. The fact that it "just died" previously would be a concern to me. Leaky intake gaskets don't cause sudden problems like that, they usually show up as lean codes and/or internal or external coolant leaks.

On the other hand, the compression numbers sound fine and the plugs are apparently OK, which of course would bode well for the overall health of the engine.

If you aren't in any hurry, then you might want to put some miles (or hours) on the potential donor motor it and then see if you still get the white smoke and good compression numbers.

Keep in mind too that a trace amount of white smoke and water coming out of the tailpipe isn't necessarily indicative of a problem.

 

I would love to do that except my donor truck is wrecked and non rivable except onto trailers etc.. I could just let it idle for a while and play around with it like that. I think that the smoke is a little more than would be common for normal engine running.

Those compression numbers were with the butterfly closed too and an engine that had cooled for a little bit. So, I don't think it would be rings, I think the bottom end is pretty good.

When it died, it had just flipped over, could have been the oil etc.., I did find that the inertia switch had not been tripped, but that it was unplugged, so either someone unplugged it at the scene or after while it was sitting. Dunno.