1970FuryConv
Old Man with a Hat
Hi WillisTo better see what's going on with the oil use issue, you might get a borescope (aka "CritterCam" on some Bulbhead infomercials, but available other places, too.) and see what's inside the spark plug hole. If the edge of piston is washed clean, then it's the (oil scraper) rings, either worn or stuck.
As for the price of a replacement engine, you might put that large amount of money toward a new mower and be done with it. Sell the old one for a bit of money, too? Or donate it to the local mechanical vo-tech school program.
As for JD, the less expensive/lower margin lawn tractors are at the big box stores, as the more expensive models at at the genuine JD lawn/garden tractor dealers. Just determine what your needs are and spend accordingly. Sometimes, getting that more powerful V-twin engine can be expensive, just for a few more horses, by observation.
Band-Aid the current one as long as you can, while you shop for a new one.
Just some thoughts,
CBODY67
I've been band aiding it for years. I had the head off in 2011 and scraped a lot of oil off the top of the piston and bottom of the cylinder head. Head gasket was mostly OK except for a blackened area near the valves. I replaced head gasket. This motor has been low quality from the beginning.