Nomad Willy
Guru
I used to do an annual change from the old school days. Since getting annual oil sample testing and being told leave it alone I stopped. I did however change the filters and that was to make me feel better about it.
I … once and awhile change the oil w/o changing the filter. HaHa
I do it because changing just the oil is so easy and quick to accomplish. With very little dust in the air in the marine environment even a small filter should have the capacity to go much longer than the oil …. Opinion.