Dead in the water pontoon/ Fuel problems

[lincolncent]

2006 90 hp Mercury 4 stroke EFI with 160 hrs. Had been in storage for a year, had Sta bil in 12 gallons of regular unleaded, added recommended amount of Lucas Fuel Injection additive along with 12 new gallons of 93 octane totalling 24 gallons. Ran fine for about 4 hrs. Shut the engine off and then it would not restart without alot of spinning over and finally ran long enough to get back to dock. Both fuel filters clogged black and all plugs were fouled and sooty. It spat out black gunk and smoked profusely before sputtering to a halt. My question, will plugs and new filters eliminate the problem and I can burn off the rest of the older fuel or should the fuel be totally drained and fresh replaced before trying to restart my engine with the new parts?

 

[SunKing22.5]

Re: Dead in the water pontoon/ Fuel problems

Sounds to me that the fuel you have is in pretty bad shape to the point where it needs to be replaced. Black filters and smoking. I do not think you should expose the motor to fuel that is causing that. It looks like you did the right things to stabilize the fuel also. Was that fuel an off brand?

 

[lincolncent]

Re: Dead in the water pontoon/ Fuel problems

Thanks for your reply. No the fuel was a major brand but further investigation into this issue let me know that corn based ethynol fuels should not be used in marine applications, something I was unaware of as I am a novice boater. I will probably drain the fuel and replace it with fresh non ethynol (corn based) fuel and see what happens from there. This time of year the filters (at least Mercury filters) are almost impossible to locate locally as other boaters are having fuel problems as well. I will post the results of my venture. Bottom line is not to leave unused fuel in your boat/engine at the end of the season.

 

[BoatNoobie]

Re: Dead in the water pontoon/ Fuel problems

that black gunk may be your fuel lines deteriorating due to the ethanol.