soulwinnerrj

Okay, so I am looking into purchasing a 1974 Gran Torino Elite, that has the 400M motor in it. This vehicle I am considering for purchase has this motor in it. The 351 was the standard, but there were several options. I am assuming this 400 is one of them... from what I have found, it was an option. For all I know, it might have a different motor in it now than when it was first bought... the owner is pretty sure the miles are 64k original... but like I said, it's not definite because he is not the original owner.


Now, with my concern... the motor smokes off and on, but isn't an issue all the time. The owner has told me that they thought it might be the rings going bad, and that sounds plausible. But, they said more recently they have noticed it is actually only smoking if the gas tank is below a quarter of a tank. They said they filled it up recently, and it stopped smoking. So they were leaning now towards a possible issue in the gas tank itself. Like, maybe there's something in the tank causing it when it gets low? I don't know... I'm no expert, but that sounds like wishful thinking to me. Or, maybe it's right... I haven't ever heard of such a thing, but maybe.

Any help on this would be greatly appreciated! :)

Thank you in advance.

George1861

IF the story is accurate, the only way fuel level would affect the engine is if there was contamination of some sort in the tank. If you confirm smoking @ 1/4 tank, drop & dump fuel, see if that solves it.
I had a car the previous owner didn't run a thermostat & maybe didn't change oil. The return holes to the sump were close to clogged. After a 1/2 hour of driving it began smoking, turned out the heads were filling with oil & getting overwhelming the oil seals on the valves.