yamaha 50hp runs real rough then dies

[willie77]

i have a 50hp yamaha motor, made in 2001. i left for iraq in 2003, didn't winterize it at all(i live in texas i didnt think it was necassary). now the motor starts after some coaxing, runs really rough, when i throttle down on it it sounds like the motor is choking out and dies. it also spits fuel out the exhaust. it does what i would call a hiccup, if motors could actually hiccup, and sounds like its sucking air but have no idea from where, just sounds like air being drawn in. i replaced the plugs and put fresh fuel in it before i had ever tried to start it. now i have tried the engine stabalizer aditive for the fuel and cleaned the carbs. it ran probably at 75% for one trip to the lake. i thought i had fixed it but the next weekend it was acting up again. any help or suggestions would be greatly appreiciated.

 

[rastoga]

Re: yamaha 50hp runs real rough then dies

If you haven't already done this...<br /><br />Your carbs probably need to be removed from the engine, taken apart, and cleaned. There are lots of little holes, floats, and jets that easily get gummed up after sitting a while. Cleaning them will help restore your motor's performance. In your situation I would replace all the carb gaskets and rubber bits to help rule out any air leaks. Carb overhauling is easy to do on your motor if you use a repair manual. Also clean/replace your fuel filter, inspect fuel lines, and clean out your gas tank.<br /><br />Try these steps and see if you still have the symptoms you mentioned.<br /><br />Good luck and welcome back from Iraq.

 

[jim dozier]

Re: yamaha 50hp runs real rough then dies

Do what rastoga suggests. The "hiccup" is what 2-strokes do when they are running lean which is consistent with a need for a carb rebuild/cleaning (gum or crud in the internal orifices). As rastoga said you cannot clean a carb properly without taking it off and dismantling it.