In Reply to: Oil pressure and tune up posted by Theo Morris on July 25, 2018 at 15:24:22:
The oil pressure gauge line is a dead-end that can accumulate junk over time and can become completely clogged. Actual oil pressure may be way different from what an ancient original or cheap replacement gauge shows. As others mentioned, "normal" oil pressure varies widely with RPM, temperature, oil type/weight, and engine condition. the manual link below shows that the factory originally recommended, but oils have gotten a lot better over the years. I run a good quality 10/40 multi-grade motor oil and the synthetic (NH-410B) combination tractor fluid year-round in Virginia.