ATV won't idle

[KJM]

My atv, an arctic cat 400, 2004, won't idle properly. she will start no problem and idle until i touch the throttle, but after that she will usually die when i let go of the throttle. I can start again by giving a little gas, but let go the gas and she dies again, even when warmed up. I had the carb off and cleaned the jets and bowl. Sometimes when she dies, if i turn her over enough without giving any gas she will catch and idle poorly for a few seconds and then seem to speed up and idle good. When his happens she is usually ok for the rest of the time i'm using her, until next startup. Any ideas what could be wrong?

 

[gm280]

I have no knowledge about how your carb is made, but I do remember years ago I had a Suzuki 300 that developed a cranking problem. If you ever got it cranked and warmed up, it ran great the rest of the day. But getting it started was the problem.

I remember removing that carb so many times and cleaning it. And the problem still existed. Then one day I removed the carb again and started looking how everything was made. Seems there was an extremely small pass-through hole in the very bottom of the carb that allowed fuel to pass through into a small portion of the carb just for cranking to allow a richer choke type issue. That little wire size hole was plugged. And I mean it was about the size of a signal strand of wire you typically have in stranded copper wire. Actually smaller then even a needle. Once I cleared that hole, it cranked like magic once again. So when you clean your carb, look for even a tiny passage that could be plugged as your problem. It won't be obvious, but it is probably your problem as well... Let us know!

 

[KJM]

Yeah, I figure it got to a carb problem. I'll have to take it off and have another look. Thanks for the suggestion, I'll see what I can find between now and first snowfall, I mostly use it for snow clearing. I have a floor to put on my boat first, the to do list is never ending!

 

[dingbat]

If it still has the OE fuel pump replace it.

Fought what I thought was a carb problem on the golf cart for over a year.

Take off carb. Clean and adjust. Put it back on. Would start and run ok for another couple of weeks.

Replaced the $18 fuel pump on a whim. Will not idle w/o proper fuel pressure. Problem solved.

 

[KJM]

If it still has the OE fuel pump replace it.

Fought what I thought was a carb problem on the golf cart for over a year.

Take off carb. Clean and adjust. Put it back on. Would start and run ok for another couple of weeks.

Replaced the $18 fuel pump on a whim. Will not idle w/o proper fuel pressure. Problem solved.

I'll definitely look into that, it still has original everything on it.

 

[82rude]

You can also check your valve lash adjustment.Did that for my bro,s kawi 360 of similar vintage and she ran great afterwards.One of many steps to look at.