2003 Mercury 9.9 4 stroke idles and dies with throttle

[COYOTE54]

My 2003 9.9 4 stroke idles fine both in gear and in neutral. As soon as I try to advance the throttle a bit it dies.

If I pull the choke on, then advance the throttle, it will increase in RPM but then start running rough until I throw the choke off, then it will die unless I throttle back immediately after taking the choke off.

I cleaned the carburetor, blew air through all of the passages.......What could it be?

Thanks,
Tim

 

[CharlieB]

Re: 2003 Mercury 9.9 4 stroke idles and dies with throttle

Your ability to get it going using the choke indicates a leanness in the idle circuit on acceleration.

Did you remove the pressed in plug to get access to the idle mixture needle and clean that passage?

How is the accelerator pump shot? An aged seal on the plunger will not give the squirt necessary for acceleration.

 

[frogseatflies]

Re: 2003 Mercury 9.9 4 stroke idles and dies with throttle

I'm dealing with the same problem on my 2005 8hp Mercury 4-stroke. Any solutions, anyone?

 

[frogseatflies]

Revisiting this post 8 years later... It was a carburetor issue. Take the carb out, clean it, and reinstall. You'll be so happy you did. Here's a video to help.

 

[GA_Boater]

You hijacked the thread 8 years ago and got away with it. Not this time.

Closed.