I replace them every year whether
Racor, CAV or whatever. The filtering element structure collapses over time and they stop being effective. I change more often, if the
engine gets more use. The same philosophy in my own
boat and in the boats I
work on.
Every time I change the filters I find quite some deposit there, be it in the element, in the bowl or in between the many
parts.
You can't have the
diesel too clean. You can only have it too dirty.
b.