Ditto. Dose up the crankcase with a healthy shot of Kroil, or possibly a pint or more of Diesel fuel added to a fill-up with cheap 30 weight motor oil. Run the vehicle a few miles under light load, but don't lug it down or do any high-RPM running. If the oil consumption and/or smoke doesn't diminish pretty soon, it's time for a teardown and probably a ring job or a more extensive rework like a rebore and new pistons if the cylinders are deeply rust-pitted.
Jerry
