water in fuel?

[eric.101]

I have a 1991 yamaha 200 2stroke. I am having to drain water seperator two or three times a trip and sometimes have to drain carbs because the motor starts to run really rough and will start shaking when I increase throttle will run at low speed fine.The boat has a 175 gal fiberglass tank and old fuel lines.I was going to change the fuel lines over the winter. I was wondering if I should use a fuel additive to help with this and witch one.Any suggestion would be great thanks ERIC

[robert graham]

Ethanol in fuels and ethanol based fuel additives will disolve fiberglass tanks. I have a rail buggy with a fiberglass tank and have to be very careful to buy gas that contains no Ethanol. Your fuel/water seperator is really working overtime for you now. Keep draining those carbs. Can you drain/flush that tank? Good Luck!

[jf123]

Check the fuel tank vent line, fuel fill cap or you purchased contaminated fuel. Ethanol will absorbe water but what your describing may be more of a sealing issue. If you can acess the fuel tank, draining would be your best option.

[robert graham]

Stabil Marine(Walmart $20/quart). Drain carbs again. Drain/pump/clean fuel tank to remove water, hopefully before it screws up carbs/motor. Good Luck!

[Tucker]

Don't know where you guys are; but here in Maryland we've had E10 for 3-years. Guys with fiberglass tanks have replaced them. In fact, insurance companies will not insure a gas boat with fiberglass tanks.