I recently bought a used center console with an ‘04 Yamaha Z200.  According to the seller, only marine grade (no ethonol) gasoline has been used in this boat.  My question is, if I decide to start using E10 fuel from roadside gas stations, what do I need to do as far as new filters or additives?  I understand it’s mainly an issue of knocking gunk loose on older fuel tanks, but I want to be as careful as possible.  I’ve also heard conflicting stories on whether the old (marine) fuel needs to be emptied/low before starting with the E10… Can ethanol and non-ethanol fuels be mixed – depending on where I fill up?  P.S. Right now the only additive I use is Ring-free…

This is a good question these days as we have all been watching the price at the pump. We would suggest that as much of the “marine grade” fuel in the tank be used prior to fueling from the roadside gas station. Starting this tank with a clean fuel filter and a spare in the boat will be cheap insurance. Keep an eye on the fuel filter for any gunk. One thing to note is that the ethanol contact of the fuel should not exceed 10%. Also, fuel containing methanol should not be used in your Yamaha outboard as it can cause damage to the fuel system and other engine performance problems. Yamalube E10 fuel stabilizer & conditioner works well with ethanol fuels.

Thanks for the question and keep ‘em coming!

Jarrett Bay Boatworks Service Department

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