Making the Synthetic Conversion on an Outboard: EFI vs DFI

[Walleye Guy]

I recently purchased a 2004 Lund 1800 Explorer SS with a 150 HP Suzuki 2 stroke motor with EFI. A friend of mine gave me an unopened gallon of synthetic outboard oil that says its for use in DFI motors. Can I safely use this in the EFI motor?

Oilman-Once this oil is gone what Amsoil product would you recommend for this motor?

[theoilman]

I don't know what brand of oil you have or all of its ratings, so I can't say for sure. EFI means 'Electronic Fuel Injection,' while DFI means 'Direct Fuel Injection.' I am not an engine design engineer (I am an Electrical Engineer by education, BSEE Va Tech), so I really am not sure about the differences or where the oil is injected, but EFI and DFI are both oil injected.

The AMSOIL for your engine would be the HP Injector, prod. code HPI which is recommended for all water-cooled marine 2-cycle engines, EFI, DFI, and can be used for pre-mix at 50-1. I didn't know that others made different oils for EFI and DFI. Perhaps a manufacturer's branded oil just says one or the other because that is the only style they make, and it still may work in both, but I don't know that for a fact.