Yamaha generator question

[snerkman]

I've got an EF2400is generator. When I did the first 20hr service, the exhaust screen and spark arrestor where totally plugged with carbon. I brought it back to the dealer - which was now under new ownership - and they told me there was nothing wrong with it. I argued with them and they even tried to bill me for their time although it was under warranty.

I took it back and within less than 20 more hours, same thing. That was two years ago and since then, I've been running it without the exhaust screen. Thing is, it hunts like crazy when idling. If you put a big load on it, it runs fine. But we usually only have a couple hundred watt load and it doesn't run smooth at all at low speeds.

When I bought my Apex last spring, I asked that dealer and he said it should purr like a kitten. My question is: has anyone else with an EF series gennie had this problem and would the 5 year emissions warranty we have on our sleds apply here. The manual specifically states that the carb is part of the emissions system so if the 5-year would apply, I could still bring it in under warranty.

BTW, the dealer I bought the Apex from is quite a distance from me, which is why I'm asking here first rather than just bringing it in.

 

[sobfrogg]

If the engine is surging or hunting for a speed you have a blockage in the carb. Sounds like the idle circuit.
The excesive carbon would make me think the same thing. Have you been burning old fuel in it?? this will cause an incomplete burn and create extra carbon.

Neither of these things would be covered under warranty seeing as they are fuel related problems.

I would bet a good carb cleaning will take care of the surging and make the little guy purrrrrrrrrrr

 

[Sled Dog]

try running some carb cleaner through it first. Look to make sure the linkage on throttle is not jamming up against something.

 

[sgilbert]

I eat that stuff for breakfast. leave the screen out, I think the pilot is right under idle screw. remove idle srew to pop it out. chase it with a wire. snip the idle mixture srew limiter and turn it out 1/2 to 1 turn. thats it

 

[sobfrogg]

I eat that stuff for breakfast. leave the screen out, I think the pilot is right under idle screw. remove idle srew to pop it out. chase it with a wire. snip the idle mixture srew limiter and turn it out 1/2 to 1 turn. thats it

BINGO give that man the prize

That'll get er done

 

[snerkman]

Thanks for the replies. As far as old fuel, it did this when it was brand new on fresh fuel.

I don't have a service manual. Can someone post a pic of the idle screw or tell me where to find it? I took the back cover off and couldn't see anything. Do you have to access it from the front?

 

[sgilbert]

pm me a pic or 2 and I'll tell you

 

[snerkman]

Thanks, but I looked up the parts diagram on the Yammie website. Should be good to go with that.

#6 - pilot jet
#16 - pilot adj screw
#26 - cap

I probably missed it because of the cap. The gennie is in cramped, dark space in an outbuilding at our hunting camp. Now that I have the diagram, I'll pull it out into daylight next time I'm there and have another go at it.

 

[fxnytro]

your breather tube is suppose to be cut during the PDI meny times it gets missed