Dear Todd;

Stay with 'standard' SAE 30 oil. Multi grade oil doesn't work well with the 'older engines'.

However; You will need to 'warm-up' in the winter months, or use an electrical device(s) to keep the oil/water temp up if it gets +30F or below (when not in use) etc.

Good luck. \:\)

John M., I.I. #3370

"There are no shortcuts to any place worth going". -Anon