2006 2.5 hp Yamaha Stalls as soon as Choke is Pushed In.

[SwillFish]

Hi,

I have 06 2.5 hp Yamaha 4-stroke that starts easily and idles smoothly, but stalls immediately as soon as the choke is disengaged/pushed-in. Any suggestions on what the cause and fix may be?

Thanks!

 

[rowboater]

Re: 2006 2.5 hp Yamaha Stalls as soon as Choke is Pushed In.

I'll take a guess and say it almost has to be fuel related.With the engine choke applied your restricting the amount of air the carbs are getting resulting in a richer mixture.Before I messed with the carb though I'd make sure there are no fuel restrictions and your using fresh fuel. Might be worth trying to pump the primer bulb and see if that has any effect on how it runs.Also may be possible there is an air leak in the fuel system but not as likely. Wouldn't hurt running some sea foam or an alternative Yamaha product that might clean up a partially blocked carb jet/passageway before getting into the carb.Do me a favor and let us know what finally fixes it as this is a fairly common problem on all kinds of motors/equipment .Good Luck.

 

[99yam40]

Re: 2006 2.5 hp Yamaha Stalls as soon as Choke is Pushed In.

I would have to say it is carb problems and needs to be taken off and cleaned properly.
Keep running it and hoping it will get better with fuel additives can cause damage to the motor from running lean

 

[rowboater]

Re: 2006 2.5 hp Yamaha Stalls as soon as Choke is Pushed In.

I would feel comfortable running the motor with a fuel additive or running the engine to isolate the problem.If the engine was run at a high RPM,under a heavy load or for an extended period of time the chances would increase in damaging the engine but 2.5 H.P. engine is about as simple as it gets.Would never want to imply running an engine lean is acceptable but for troubleshooting purposes sometimes a motor has to be operated in less than ideal conditons.Chances are it is a carb related issue and it will have to be taken off and cleaned properly.I just personally would not be in a rush to rebuild or clean it before ruling out a simpler fix.If running the engine in it's current condition is a concern you could always pull the spark plug and see just how lean it is running.

 

[SwillFish]

Re: 2006 2.5 hp Yamaha Stalls as soon as Choke is Pushed In.

Thanks everyone for the feedback. I tried to run it again with a fresh gallon and am still having the same problem. We also put an ounce of Sea Foam in the tank to see if perhaps that might improve things, but I'll need to run it for a while with the choke open to find out. The last thing I'll try is to pull the carb and send it in to get cleaned and serviced. My guess is that that is probably it. It may take a while, but I'll be sure to let everyone know.

 

[Erin]

Re: 2006 2.5 hp Yamaha Stalls as soon as Choke is Pushed In.

I would like to share a similar problem, same make and model.

Without any choke, I get an immediate start and low speed seems fine. When I throttle up, kicking into the high speed range, the RPMs just don't kick in. It appears to be running very rich, and leaves a black soot residue.

In addition, when I close the fuel shut off, reducing the fuel in the mix, the RPMs creep up and then really escalate before stalling.

I have put in a carbi kit including jets. It was thoroughly cleaned and blown out.

I read somewhere that the float needs to be set. Does anyone know about this? Or does anyone have an idea what I am doing wrong?

 

[Erin]

Re: 2006 2.5 hp Yamaha Stalls as soon as Choke is Pushed In.

One last item, I have already tested adjusting the factory set air mix, through the full range and then back to the original setting.

 

[99yam40]

Re: 2006 2.5 hp Yamaha Stalls as soon as Choke is Pushed In.

1st problem I see is you posted on an old thread