Our 1991 P42 that we purchased in 2002 came equipped with a Yanmar 4JH2-TE tractor diesel and an Onan Cummins (Kubota three cylinder tractor diesel) 8KW Genset. Both have been very good performers over the years. Each engine has its own fuel filter; a spin on canister on the Yanmar and a cartridge filter on the Onan.

The PO had installed an after market Dana 33390 fuel filter on the Yanmar and the Onan OEM was a two micron cartridge original equipment. Rather than purchase OEM spares I opted for NAPA brand spin on canisters as an alternative. Hunter installed Racor ten micron cartridge filters for both engines between the fuel tank and engine filter.

Professional transportation diesel mechanics advised me that six micron fuel filters would be more than adequate contamination protection for any diesel engine. NAPA brand fuel filter part numbers of both engines follows:

Yanmar: OEM 129470-55702 five micron canister filter.
Yanmar: NAPA 3390 ten micron canister filter.
Onan: NAPA 3426 six micron canister filter.
Racor: OEM 110 ten micron cartridge filter.

The Yanmar currently has 1,700 hours and Onan 450 hours.