Living in Alaska were temperatures range from -20F to 32F in the winter and 40F to 70F in the summer. I have been using Aero Shell 15-50W year round. I was wondering if I should change to a straight weight oil in summer. Currently I am changing #1 cylinder for low compression 53/80. Not sure if I have a burnt exhaust valve, cracked cylinder. Leakage is in exhaust. I preheat engine when temperatures get below 32F. Engine type is O320-150hp?
Any thoughts?
Happy flying.
