3hp gamefisher

[falco]

just bought a '91 3hp gamefisher for my 10' boat. It runs perfectly while it's out of the water (it's air cooled) but will "bog down" and die when you put it in the water.

It will idle okay, but once you start to increase the throttle it will bog down and shut off, it doesn't matter if it's hot or cold. Once it shuts off it'll start again with just one pull and go another 200 yds or so before it shuts off again. I opened everything up expecting to find a gummed up carb, but it was surprisingly clean. I couldn't find anything restricting flow of fuel or air. It's got plenty of compression and everything turns smoothly.

This is one of the models that doesn't have a muffler. The exhaust it just piped down below the water and comes out a couple inches above the prop. My question is....i know it's designed to function that way, but could the backpressure put on the exhaust by the water be causing the problem? It has a few small holes drilled in the exhaust pipe above the water level to relieve some of the pressure....if this turns out to be the problem all i'd have to do is drill a few more holes and it should run fine.

The problem obviously has something to do with the resistance from the water on either the prop or the exhaust, because it's only an issue when the motor is under load. I'm just at the end of my knowledge. maybe one of you guys have some experience with this.

[Barnacle Bill]

I suspect the carb needs to be adjusted. In the water.

[KrappieKrane]

Falco, try removing the carb and disassemble the unit all the way down. Buy a bucket of carb cleaner and submerge for a couple of days. It seems you make have a restricted jet and the cleaner will remove all the varnish you can't get to. Don't get the cleaner on you hands also. It will peel the hide. Good luck and hope this helps. Rollcaster...............

[Fisherman_Wantabe]

Seafoam Deep Creep! Remove your air filter from the carbs and spray the deep creep into the carbs while running till it's smoking like crazy. Do this three or four times and start using Seafoam in your fuel. Just my 2 cents.
Seafoam is some sure enough good stuff

[beenfishin?]

inspect any fuel hoses/connections for pinholes. Only takes one to cause your troubles.