Anybody know anything about boat motors?

[trevell407]

I took my little jon boat out today and the motor started acting up when I was on my way back to the dock.
Its an older 25hp mercury, probably early 90's or late 80's.
I was cruising at almost full speed when it started to bog down,
the ball pump thing in the fuel line wouldnt stay inflated and there was still 3 gallons of gas left in the tank.
I tried fiddling with the connector on the gas line that hooks to the gas tank because I thought it wasnt letting gas through but it seemed to be working.
Anybody have any idea what it could be?

Thanks much, Trevor.

 

[Dannyboy]

Sorry Trevor, I know boats pretty well, but mainly inboards and I/O's. Has the motor been running recently or has it been sitting a while?

When I worked for a boat dealer it seemed like lack of use caused common problems, specifically clogging up the carb and clogging up the electric fuel pump. (one mfg. did not use fuel stabilizer after lake testing brand new boats and we were rebuilding/replacing brand new fuel pumps all the time).

So it sounds like it could be a fuel delivery problem. Was it dying on you? Where you able to re-start? Will it start now?

 

[manaen]

If it was sucking the bulb together the breather on the tank must be clogged which is ultimately starving your engine of fuel. there should be a small pinhole or an actual valve(on some tanks) that needs to be open to allow air to flow into the tank as gas flows out. Otherwise a vacuum will form in the tank and not allow the engine's small fuel pump to suck the gas up to the carb.

That would be my guess

 

[Donner]

Now, if someone could answer this question with as much fervor as they do to point out when I'm incorrect, that would be nice! Let's see, who knows about boat engines?? $4,000 in fuel??

 

[manaen]

Huh? have you been drinking your post is slurred

 

[Donner]

nah, don't worry about it... someone was giving me a hard time, so I figured they'd step up and answer the questions here. it's alll goood!