Coleman Outboard Problem

The son of a friend of mine bought a new 5hp coleman 4 stroke for a small jon boat. He has taken it to the river twice and both times , after about 10 pulls on the starter pull cord, it would crank and run fine for about 20 minutes. It would then quit running and never start again while at the river. He would get the boat/motor home and it would crank and run in a water filled garbage can again for about 20 minutes. This motor has the built in .31 gal tank. There is a fuel vent on the cap and it will also work with a remote tank. I went with him this morning and the motor cranked after about 10 pulls on the starter pull cord. We rode for 23 minutes and the motor died and we could not get it to restart. The onboard gas cap vent was opened as instructed, The valve for remote fuel tank was in the correct position. Kill switch/lanyard was in place. The primer bulb was firm. I disconnected the fuel line where it attaches to the carburetor and pulled the pull cord and gas was pumped out of the fuel line. I am getting gas to the carburetor. I pulled the spark plug. I did check to see if I am getting spark at the plug and I am. I replaced the spark plug, make sure all settings were as instructed in the owners manual, primer bulb firm and then pulled the starter rope. It would hit about 3 time as if trying to start, then nothing until I removed the spark plug again looking to see if its wet with fuel. Put the spark plug back in and it would do the same thing, hit about 3 times then nothing else. He had a heck of a time trying to find a service/warranty center and the service man said that after he ran the motor for about 10 minutes he could not find anything wrong. Does anyone have any suggestions about a possible fix for this problem. When its running, it runs good, but why is it consistently dying after about 20 minutes. As of now he only has a little over an hour run time on the motor. Thanks Larry

You might try cleaning the carburetor. There may be some debris in the bowl that plugs the jets after running about twenty minutes or bouncing around while under way. After the trip home the gas in the bowl sloshing around may be dropping the debris back into the bottom of the bowl. When you pulled the plug was it wet? If not it may not be getting fuel or enough fuel from the carburetor. It being a four stroke you could try to shoot a little starting fluid into it and see if it fires on it. Do not shoot a lot into it, just enough to see if it fires. If it fires you have a fuel problem.

KMixson, Thanks for the reply, I also believe its a carburetor related problem, Thanks again

I had the same problem with my Tohatsu 4hp 4 stroke. It was a dirty carburetor along with some bad gas. Cleaned the carb and switched to premium & no more problems.