Carburetor spitting fuel out, running rich, is it fuel pump?

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Incahiker

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Alright guys, pretty much pin pointed my problem on my motor. I know a lot of people will pull the choke out to see if it is running too rich. Well when I do that my motor boggs down even more. So I did the opposite, I closed the fuel supply off, and for about 10 seconds my motor is running incredible, it is screaming at a high rpm and I am running at 10 mph in my 15 foot tracker (ya, I know it's not that fast, but it is way faster then it was, lol.

So obviously the motor is running way to rich. Also, when it is running there is a lot of fuel being spit out of the front of the carb where it breathes the air. I had already taken the carb out twice, cleaned the snot out of it, and checked the float twice. Do you think the fuel pump is faulty. It is a 1989 4hp mercury made in Japan.
 
Could it be the float? it idles great, it just has problems at high rpms. Like I said, once I shut off the fuel valve the carb will run great for 10 seconds, suggesting that it is running way too rich. The motor also starts up on first pull every time.

If I pull out the choke while motor is running it will die immediately. I thought that a bad reed would make a motor run lean?
 
I take it there is no adjustment for the high speed circuit? Probably not. On the fuel spit issue, don't put too much into that phenomenon (as long as is isn't a copious amount) as the OMC 3-cylinder engines did that religiously at speed. Several other model engines would do that as well. You may want to think twice about checking the reed or reeds as has been mentioned. If the engine idles as well as you say I doubt that you will find anything as reeds will normally affect idle pretty drastically as well as starting.
 
Well,
I dug into the carb and the float was definitely set WAY too high, where too much fuel needed to be in the bowl to clove the needle valve. I set it to the right height and put it back in.

The odd thing is that the motor will run strong when cranked cold. But once warmed up after you shut it off or idle for a while it gets kind of sluggish. Then I take the cowling off and it runs like a champ again. But, if you let it cool off for a while and then run it, it runs really strong and will stay really strong as long as you keep full throttle going. If you get to idling around like trolling for a while it will get sluggish when getting up to full speed, unless you pull the cowling off. But it is running much better then before. It is getting me places way faster then any trolliing motor would so I am not complaining, lol, especially for the price I paid. And the motor cranks of the 1st try every time, and idles great, better then any 2 stroke motorcycle or outboard I have had.


Well... I was just thinking, after idling around for a while, and then it seems to slow down.... does it sound like the idling around on my 2 stroke is fouling the plug?
 
Have you checked the impeller and thermostat? It could be slowing down due to overheating.
 
Your motor is still running too rich. I was working on an outboard the other day and it was running terrible. It would idle fine but around half throttle it would start bogging. When I removed the cowl it would pick up some but still not run like it should.
The problem with this motor was a faulty fuel primer solenoid which your motor does not have so you need to look elsewhere.
Since your motor is running better after tweaking the float I would go back and tweak it some more since that's probably where your problem lies. If you haven't bought a carb kit for it I would do that as well.
 

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