I bought a brand mini airboat w/40 kohler. The boat looks exactly like the picture on this homepage. Bought it last march. Used it 3 times in March. It ran perfectly and have not turn it on until now. I can't get it started so my buddy helped me clean out the carburator. it is all clogged up. Got it started, took it to the river but it died when I rev up to 2500 rpm. appears to be lack of gas to I bought a brand new electric fuel pump from Kohler (Facet 7gph, 1 to 2 psi) , installed it and back to the river. It die when I rev up to 3000 rpm. again, it appears that the carburator is not getting enough gas. Could this fuel pump be too week even it is what Kohler recommended but might not work for airboat application. Could someone help me troubleshoot this problem. I am an engine idiot so please be patient.

Thanks,

I would think with it setting that long, the complete fuel system would need to be cleaned. I would drain the fuel tank and put some fresh 93 Octane in it. The carb may have to be put in a cleaning tank and let it set for awhile. The ethanol fuel that's sold now will seperate in 2 months are sooner in high humid conditions.
Thanks, Chuck

Ethanol not good for these small engines... if you can get ethanol free get it.

stripermania,

Like Chuck said, if it sat for a year with gas (ethanol or not) in the carb, the carb will need a very good proper cleaning to get it back going right. And you'll need the tank full of fresh gas when you try it again.

One way to avoid this in the future is to disconnect the fuel line and run the engine (at idle) until the carb runs out of gas. Then put whatever gas is left in the tank into a car, truck, lawnmower. Just use it up.

This has always been a problem. Gasoline goes bad over time. The ethanol blended gasolines are even worse than what we had to deal with in the past.

Good luck with it,

Duane

I like the E10 Ethanol if you use your boat every week. The Ethanol will keep your fuel system clean if used often. It want gum up like reg gas. The problem is when you don't run the engine and let it set for long periods of time. The Ethanol will settle to the bottom of the tank and leave the degraded gasoline on top. The pure Ethanol in the bottom of your tank will attract moisture that sets in the bottom of your tank. When you run it, the water droplets will stop up the jets in your carb and the engine shuts down. You blow out the carb and then it runs until another water droplet showes up. Thats why you need to clean the complete fuel system.
When adding 10 % Ethanol to Gasoline to get what is called E10, You are adding a cleaning agent to the gas. You are also adding 3 Octane which means they take 90 Octane Gasoline and add 10 % Ethanol to it and now you have 93 Octane fuel. When it sets for long periods of time and the Ethanol seperates, The gasoline on top is now a substandard gas at 90 Octane. Thats why just draining off the fuel in the bottom of the tank want help that much.
If i want to store a boat for months, I take all the ethanol out and put a couple gallons of AVGAS in, crank it and let it run about 15 minutes. Shut it down and 4 months later it will crank and run.
Thanks, Chuck

Thanks for all the help. I forgot to mentioned that the fuel I am using now is new. It is 89 octane. So I guess the Carburator is really bad and I have not throughly clean it. I will buy a new one and take this one off to clean in the mean time. two more questions.
1. I put the electric pump on the boat floor on top of the Aluminum T and run a 5' 1/4" hose to the carb. is this location OK ?
2. Is the Facet 7 gph, 1-2 PSI sufficient for this 40 hp Kohler ?

Thanks,

on our bowfishing rigs we use a low psi electric pump. I bypassed the original diaphram pump on my 24hp honda and use an electric pump from NAPA autoparts. I do not reccomend MR Gasket pumps--mine ran 10min and died and others have had similar problems. I've had no problems w/ the NAPA pump.

I'm a huge fan of sea foam fuel stabilizer and have had tremendous success using it in my snowmobiles to keep the gas with ethenol stable. We ride our sleds for about three months at most here and the rest of the year they set outside in the yard. I know that allot of small engines can be damaged from some fuel additives but SeaFoam advertises that it is specifically engineered for small engines.. I've never had a problem with it.