Motor Trouble?

[wdgold]

I have a 1991 100 mariner outboard. Went up to whitefish chain and that is when the trouble started. The motor runs perfect at idle and when you are trolling, I test ran in my driveway at home and everything seemed good, but when you go to full throttle I can get about 7 mph out of it and the motor is missing severely. This motor has the 2/4 system on it. I don't know if the cylinders are starving for fuel or if it is an ignition problem. I had fresh premium gas in it and I changed the plugs. Any help would be apreciated.

Thanks

[RedDB76]

I'm by no means a boat motor mechanic - but I had a similar problem with my 1986 90 hp Merc last summer, and it ended up being the stator. It fixed some of the hard starting problems I had been having since I bought the boat as well.

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[Surface Tension]

Thats going to be a hard one to diagnosis over the internet.

From your description I think you have an electrical problem. Idles fine, misses bad at full throttle, can't get any speed. If it were starving for gas it would bog not miss.

If it were running rich and flooding then that show up at idle speeds as well.

If your going to take on the problem you'll need a manual to begin troubleshooting and testing.

[monticello coach]

i had the same problem last year......it was the ignition

only cost about $100 to fix

[wdgold]

Well my motor is fixed the carbs were adjusted and that is all it took the motor runs great. I do appreciate all the input from everyone this site is great.