Scantlings

The oil and filter on my boat were changed last fall. Since then, I've powered far enough to burn approx 5 gallons of diesel out of my 20 gallon tank. I usually change the oil and filter every fall, and I understand about oil "going bad" with time as well as with use. But....

Do I have to change filter this fall? On the one had, it's had very little use; on the other hand, it does hold a non-trivial amount of oil. What say you?

SemiSalt wrote:The oil and filter on my boat were changed last fall. Since then, I've powered far enough to burn approx 5 gallons of diesel out of my 20 gallon tank. I usually change the oil and filter every fall, and I understand about oil "going bad" with time as well as with use. But....

Do I have to change filter this fall? On the one had, it's had very little use; on the other hand, it does hold a non-trivial amount of oil. What say you?

I generally don't like to leave used oil in the engine over the winter, since it does pick up acids and junk from running, but with that little time it should be fine. I'm probably going to change my oil in spring, just because I can't do it now. It also has very little time on it, dammit.

Oil from a diesel, especially an old one, can have a lot of contaminates from combustion even after only a few hours, including acids that attack the chromium hardened parts. Oil is cheep. End of season is also the best time to do your oil analysis. Having a good trend line helps with the diagnosis and prevention of other problems.