Mercury 40 hp won't idle

[extraequipment]

Hey everyone, we just got a "new to us" boat with a 40hp Mercury Force(1995 i think?) but it won't idle. When we start it, we have to push the throttle far into forward to get the mercury started. Once we idle it down into neutral, it'll sputter down and stall. At higher rpms the engine runs very smoothly, but low rpms will stall the engine out. Any ideas?

 

[Wingedwheel]

Re: Mercury 40 hp won't idle

How long had the motor been sitting before you got it? It sounds like you may need to clean your carb.

 

[extraequipment]

Re: Mercury 40 hp won't idle

About a year? I sprayed some carb cleaner from Autozone into the engine? I really doubt that did anything though right?

 

[Wingedwheel]

Re: Mercury 40 hp won't idle

To properly clean it you have to dis-assemble it. Its not hard and always worth it. I'd also suggest getting a manual. You'll be doing yourself a big favor.

 

[nicknight]

Re: Mercury 40 hp won't idle

+1 on the manual thing....worth every penny
+1 on the cleaning carb thing.....it is not THAT easy, just be cautious
Also...maybe the throttle cable is not properly adjusted

 

[GailT]

Re: Mercury 40 hp won't idle

We have the same problem. We were going along at full speed and it just quit. Changed plugs, gas filter and line, etc. Now it is doing the same as yours. Did you find anything out?

 

[BatDaddy1887]

Re: Mercury 40 hp won't idle

...at the very least try a cup or two of Seafoam or Quickleen in the gas tank to help clean out the fuel delivery system (maybe check the fuel filter, or old hoses sucking air).

 

[GailT]

Re: Mercury 40 hp won't idle

We did put SeaFoam in it, that didn't help

 

[extraequipment]

Re: Mercury 40 hp won't idle

Hey All, Thanks for the advice. GailT, ours wasn't as bad as just quitting, but putting it in our dock slip, etc. was a pain. Basically, we did what you all said, and used the Seafoam. That stuff helped TREMENDOUSLY. We also raised the idle so it would stop stalling. It has never run better. Were tubing on it now and we just bought a kneeboard. For a 40hp, the little pontoon can fly.

 

[BatDaddy1887]

Re: Mercury 40 hp won't idle

....let the good times float...!!