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Bad Gas?


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I have a 1990 Evinrude 88 Special outboard. It's a 2 cycle and I've never had mixing problems whether I fill from cans or at a pump and add the oil afterwards.

The other day I got gas at the marina's dock for the first time this year. Since then the boat has been dogging it and won't go over 17 mph. It feels like it gets a shot of clean fuel and speeds up, then dogs back down. It was running perfect every day all week until I fueled up there.

I'm thinking bad gas. It's home now so I plan to add fresh gas, some dry-gas, clean the plugs.

Any other thoughts?

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First off, see if the gas from the marina had ethanol, if so you can cancel the dry gas. Second, I think everyone will agree, if you don't already have one, get a fuel seperator. Third, don't bother cleaning the plugs. Take it from a guy who's run two strokes all his life, you will never get them 100% clean and only invite problems down the road, just spend the $3 each for new. If you do the above and still have problems, then it's time to start looking at the motor.

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How long since your fuel pump was rebuilt ???? Next time out have some one pump the primer bulb if it picks up speed your diapharms are shot in the fuel pump. Also check for air leaks from the tank to the motor , kinks or weak spots in the supply line and change all fuel filters..................I just went thru this whole deal and also changed plugs like he said above.............one other thing I did was run carb cleaner on all three of my carbs with the water hose hooked up.................good luck...........

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As always,check the cheap problems first.You have no problem starting or running at idle and low rpm.So that part of your carburetor is clean and you get enough fuel.

Now unscrew the high speed fuel jet.(the one on the carburetor bowl),drain the fuel in the bowl and make sure that the jet and the bowl are clean.

Now disconnect the line that goes from the pump to the carbs.Pull the plug wires and pump the ball.Fuel should stream out. If not ,you have localized your problem.Now run the starter.Fuel should come spurting out of the pump .If not, your diaphragm is bad or you have dirt in the filters.You can do all these things at home in your drive way and depending on the results of these little trouble shooter tests you can determine where your problem is located

If you are on the water and it happens again,push the starter key in.This will activate the fuel enrichener.If that helps you know that your problem is not bad fuel but fuel supply.

If nothing is wrong with the fuel or the fuel supply,it is time to look at the electronics.

Good Luck,


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