1986 force 50 outboard uses excessive fuel

[littleTommy]

Greetings - I just purchased a 1986 Bayliner with a US Marine Force 50 outboard motor and am concerned about the amount of fuel it is using. It runs fine but smokes excessively and used about a half gallon of fuel every 10 minutes just idling. I adjusted the idle screw and that helped things. I also re-seated the float bowl on the gasket to fix a leak from there.

Does anyone know what is causing the carburetor to be dumping fuel into the cylinder like it is?

 

[Jiggz]

Re: 1986 force 50 outboard uses excessive fuel

You might want to check the air screw setting although this is something you have to have a good understanding before messing with it. The reason is that if improperly set if can cause significant damage to the engine. Try reading the link and synch sticky post first to have an idea what the air screw does and how to adjust it. As for the heavy smoke, it could be due to too rich of air fuel mixture or due to carbon buildup in the engine. check your spark plugs if they have carbon build up.

 

[littleTommy]

Re: 1986 force 50 outboard uses excessive fuel

Good news here. I suspected that there was an issue with the fuel pump since the carb looked clean when I took it apart. I bought a new $4 diaphragm for the fuel pump and replaced it. Motor runs great now and is sipping gas like it should. I took it out and ran it about 30 miles and it only used a couple gallons of gas. Good little motor now.

 

[rollincbmods]

I know this is an old post, but I wanted to put in my two cents because I had the same issue and found the problem.

I have been chasing excessive fuel to my carb for a year. No fishing for a year, I have wanted to cuss and cry all the time. I got the correct carb for the motor and replaced the needle/seat and float assembly. I still had the same issue, too much fuel, flooding engine. I finally got the engine to run if I set the throttle to high idle, but would only idle regular after it was up to operating temp.

I pulled my fuel pump off today and found a big hole in the diaphragm thanks to this post. Y'all were a life saver. I was ready to give up on the boat and pick up another one just to ditch this issue.

I ordered a diaphragm and gasket from Crowley Marine today for $18. Thanks to the wonderful insight from this group I will be back on the water very soon. Thank you very much.