Using oil issue
Hard to say what is going on with your rings seating after sitting for that much time.
Who's to say it was even overhauled 4000 miles prior, people will say anything when trying to sell you a car.
Have had great luck with the "Seafoam Treatment" to free up carbon stuck piston rings on many oil buring engines.
Put a pint of seafoam in the engine oil and let it run at a fast idle for 1/2 hour.
Change that oil out with some thin 5w30 motor oil and new filter. Put another pint of seafoam in with the new oil and take it out and drive it for 50 miles. You need to work the engine to heat it up and expand out the piston rings to help them reseat to the cylinder walls.
Get back and drain out that oil when it is warm and put in your regular grade of 10w30 or 10w40 motor oil and a new filter.
Then go to driving again.
____________
For worse cases that are smoking while idling, pull the spark plugs and pour in 1 ounce of seafoam into each cylinder and let it set (soak) for a week to dissolve the carbon in the piston ring grooves.
Put the plugs back in and do the above process for the final clean up.
The oil coming out will be really black from the removed carbon.
Have successfully done this on many engines to stop the oil buring.
Even a nasty dirty diesel old tractor that was smoking at idle at time of purchase. Had to put 2 pints of seafoam in the engine oil and run it up warm for a 1/2 hour, let that one set for 2 weeks to soak.
Injectors on those diesels so can't easily pull spark plugs like gas engines.
Followed up with the same process as above, cleaned it right up. Still not smoking to this day, keeping the oil and filter changed on a regular basis.
☆☆☆☆☆
Hard to say what is going on with your rings seating after sitting for that much time.
Who's to say it was even overhauled 4000 miles prior, people will say anything when trying to sell you a car.
Have had great luck with the "Seafoam Treatment" to free up carbon stuck piston rings on many oil buring engines.
Put a pint of seafoam in the engine oil and let it run at a fast idle for 1/2 hour.
Change that oil out with some thin 5w30 motor oil and new filter. Put another pint of seafoam in with the new oil and take it out and drive it for 50 miles. You need to work the engine to heat it up and expand out the piston rings to help them reseat to the cylinder walls.
Get back and drain out that oil when it is warm and put in your regular grade of 10w30 or 10w40 motor oil and a new filter.
Then go to driving again.
____________
For worse cases that are smoking while idling, pull the spark plugs and pour in 1 ounce of seafoam into each cylinder and let it set (soak) for a week to dissolve the carbon in the piston ring grooves.
Put the plugs back in and do the above process for the final clean up.
The oil coming out will be really black from the removed carbon.
Have successfully done this on many engines to stop the oil buring.
Even a nasty dirty diesel old tractor that was smoking at idle at time of purchase. Had to put 2 pints of seafoam in the engine oil and run it up warm for a 1/2 hour, let that one set for 2 weeks to soak.
Injectors on those diesels so can't easily pull spark plugs like gas engines.
Followed up with the same process as above, cleaned it right up. Still not smoking to this day, keeping the oil and filter changed on a regular basis.
☆☆☆☆☆