Mariner 40BE will not stay running

[Drewzr14]

Hello everyone,

Thank you for taking the time to read my post.

I have a japan Mariner 40BE outboard motor that just will not stay running. I can get it to start and it will idle for maybe 15 seconds then just idles down and quits. If I run it in gear and throttle up and down (rev it) I can get it to stay running longer but it will eventually stall out.

I have clean gas (non-ethanol) and am running Sea Foam in it.
I have sprayed Sea Foam directly in the carb while it's running as well.
I bi-passed the in-line fuel line filter and nothing changed.
I cleaned the cup element filter although it was pretty clean anyway.
New spark plugs.

Could this be a bad diaphragm in the fuel pump?
Or should I take the carb apart and clean it?

Any ideas would be greatly appreciated!

Thank you
Drew

 

[JDusza]

Re: Mariner 40BE will not stay running

What's the history of the engine?
New to you? First time you run it?
If stale gas is varnished in the carbs, SeaFoam may eventually clean it out but it's not instant.

Can you pull the fuel line from the fuel pump to the carb at the carb. Wrap it in a rag. With the ignition dead, crank the engine. Fuel should squirt into the rag.

Can you squirt premixed fuel into the carbs and keep it running?

My first would be cleaning the carbs. Might be sticky inlet needle valve.

 

[Drewzr14]

Re: Mariner 40BE will not stay running

History: I bought this motor and when I did it ran just fine. I stored it a couple years and am taking it out to fix it up and sell. There was a mouse nest in the engine and a few wires were chewed that I fixed.

I was able to keep it running by squirting SeaFoam directly in the carb every time it started to idle down and die. This would rev it back up again and stay running. Do you think I should try squirting pre-mixed fuel into the carbs to keep it running long enough to clean the needle valve? Or would it be better to take the carb apart and clean it. Is that very difficult to do? I'm pretty handy but usually don't mess with carbs.

Thanks for your reply ~

 

[Drewzr14]

Re: Mariner 40BE will not stay running

I pulled the carb.. there was no way seafoam was going to solve the problem. There is some white crusty stuff in there so.. time for a carb kit.