(quoted from post at 13:20:04 12/07/18) There is about a pint I think of this substance and it floats on top of the antifreeze. I put some on a spoon and heated it and the antifreeze evaporated and a what looks and feels like oil was left. I may try to do the oil passage test if I can get the right set up. What do you look for after you spray the thinner into the oil passage, the color in the radiator?
So what are you trying to accomplish here?
You start out by stating "it ran good, but smoked a little".
Is a 'little smoke" an impediment to what you want to do with the tractor, and how much $$$ are you willing to toss at it?
A little oil in the coolant (if that's what it REALLY is) hurts NOTHING, of course antifreeze "in the basement" is another matter.
Another thing... how long since the coolant has been dumped, the system thoroughly flushed, and new coolant installed... if a few months, you've probably got a problem, if 10 or 15 years, maybe not so much.
If you want to thoroughly and correctly "overhaul" it, and make it "as new" you can easily toss more $$$ at it than the tractor is worth.
On the other hand, as a long-time denizen here, I have read MANY sad stories of these poor machines ending up FAR worse after an botched or low cost attempt to make things better.
You MAY have a head gasket that is slightly leaking combustion products into the cooling system, If I suspected that I would do a "warm re-torque" of the head fasteners before trying anything else.
The oil gallery is below the waterjacket, and it would take a really unique casting defect or crack to create a passageway from the oil gallery to the waterjacket, but it has been RUMORED on there that it can happen, don't ever recall a post on here definitely confining that someone had found this "in the wild", but anything is possible.
You state the amount of "oil" was about a pint. Once again, how long since a flush and coolant change?
If YEARS, and quite a few hours of use, how small would a leak or crack between the oil gallery and the waterjacket have to be to limit the amount leaked to "about a pint", would be long shot to track down a leak that small, it would seem.
I would torque down the head, flush and refill the cooling system, and run it and WORK it and put some hours on it, then check things out and reevaluate what I wanted to next.
But, for the old tractor's sake IMHO, don't just tear into it, throw a few parts at it, and expect it to be better.
But if you have the desire, the experience/knowhow, the equipment to R+R the sleeves, the $$$ and know of a good machine shop to boil the block, thoroughly check it for cracks, check the linebore, check and recondition the rods and the oilpump, grind the valves, you will wind up with a really NICE $2000 engine.