Suggestions appreciated...

[Scott S]

My little Jon boat motor started acting up Sunday and as of today had not fixed itself.
It starts hard when warm and wants to die when throttled down. Starts good when cold and runs out good.
Do you think the decarb procedure with Seafoam would be a place to start in trying to tune it up?
Decarbing Your Engine- The Process-HOW AND WHY - iboats Boating Forums
It's a 1976 Johnson 6hp.
Scott

[Prowler]

Hmmmm... not sure about a procedure to help you... although using seafoam has certainly helped me before...


BUT... I think you may seriously want to consider upgrading your motor... I dont think that it has enough horsepower to effectively plane out that old jeep. :D:D

[Scrapper]

LOL...thats a cool pic!! I love a Johnnyrude!

Sounds like I would check the water pump. Sounds like she may be getting hot...if hot starts are hard to do and cold are good. Also may be looking at a carb job...then run seafoam.

[MSHLS]

One thing you may want to check is the coil, plug and plug wire. I had a problem with a mower doing the same thing as your outboard ended up the coil had a small crack that got larger when it heated up.

[Scrapper]

Thumbs up on what MSHLS says.

Electronics that are getting weak or fatigued DO NOT like heat. Check all that over good.

[thudpucker]

You can check the heat problem easily. Just hold your hand under the exhaust for a few seconds. You should feel water in the exhaust, and it should not be so doggond hot you cannot hold your hand under there.

Make sure I have this straight, you can start it when cold, and it will run well for a long time.
But when you try to idle down, it dies?

Without your answers I'd say you have to get that carb off there and clean out the low-speed jet.
The other thing that goes wrong with those great little motors is the fuel pump. Although if you use it often, normall thats not the problem.
You have some gunk in the carb, and when you find that gray crap down in there it sometimes has to do with the Gasahol you get from the pump.

Of course we are assuming your hoses and filter (if you have one) are in good shape.

PS; I dont know what sea foam is. I've never thought there was a ghost of a chance that anything you spray on the outside of a Carb, or pour into the Gas would ever do anything to clean out a clogged jet orfice.
I've always done just what I suggested, and it works.