1989 115hp outboard problems

I have a 1989 Mercury 115hp inline 6-cylinder and I have trouble when trying to take off the engine feels like its going to stall and will at times. I have replace all the main fuel lines coming to the disconnect, fuel filter and primer bulb. It seems as if it won't stay primed when connected to the engine. I can pull the line off the disconnect and can prime it with my finger over the end or if I put a hand pump on the end of the line it will prime and fuel will stream out until I close the tank ball valves off. I have checked the intake pickup lines and they are fine. I am suspecting its either a fuel pump issue or a disconnect issue. Wondering if anyone else has experienced this and what should I do. It will start and run ok in neutral I can rev it up and everything just fine. I put new gas in after dumping the old out and cleaned the tanks. I used a 50:1 ratio on the fuel to oil and I even put seafoam in the fuel as a treatment. I Think this is the fuel pump I have not sure http://www.crowleymarine.com/mercury-outboard/parts/278_12.cfm Please help!

Thanks,
Jason

Re: 1989 115hp outboard problems

Have someone pump the primer bulb why you try to accererate. If that fixes it, rebuild the fuel pump. If not, then the carbs are a suspect.

Re: 1989 115hp outboard problems

Might be you just have to back out the carb screws an 1/8 turn and all will be well. I'd try that first in 1/8 turn at a time on all three carbs at the same time. Cheap and easy.

Re: 1989 115hp outboard problems

also make sure your fuel tank is venting properly nothing clogging hole , play with idle screws to specs ??? Id bet its either the fuel pumps or ur tank isnt venting properly ...

Re: 1989 115hp outboard problems

I have spoke to a couple of boat mechanics and one seems to think it could be compression where is the other seems to think it could be something related to the fuel pump the guy that thinks its compression wants me to check the compression in the Pistons because that's how the fuel pump operates he said he's having them blow up left and right out on our lake because of the fuel it's been raunning however I told him I ran Ethanol free he said that didn't matter... out of the two exhaust ports on the back of the engine while idleing you can see little droplets of fuel hit the lake I don't know what that means can anybody help.. also want to add I think its actually a 1984-85 model

Re: 1989 115hp outboard problems

If raw fuel is being dumped into the water, that is a good indicator that the fuel pump diaghram is torn. Sounds like rebuild time for the fuel pump.

Re: 1989 115hp outboard problems

Thats what I thought originaly... I will check the compression to be sure and then rebuild it.