I bought a barely used 2006 Arctic Cat 50 Utility (4 stroke Kymco) and I'm having big problems with the carb. The original owner said it never ran right to begin with. I've taken the carb apart 3 times and cleaned it very well each time (soaked, blown, wired, ect). The engine is surging and I'm wondering if it has to do with the electric choke. I've adjusted and adjusted both screws and this thing will not settle down. I've been doing searches for a couple days now and it seems like these electric choke carbs are just a huge problem. To be quite honest, my brain is fried from all the searching so I decided to register and post. This is dangerous for my son as it will rev up by itself and actually lung forward so I haven't let him ride it yet and he's about ready to blow a gasket!

My question is what should I get for a replacement carb or is there something I'm missing? I'm tired of messing with this thing and just want to get rid of the electric choke and go with a manual (preferably with choke cable that I can mount on the bars or somewhere else). This is not going to be used for racing so I don't need a extremely expensive replacement. If I'm barking up the wrong tree, please feel free to let me know. Any direction is much appreciated!

JG



Link to schematic of carb AC 50 carb

 

Are you saying it is idling high and you can not get the idle to go down when using the idle adjuster? Or is it idling high then low for no reason? If you can not get the idle to go down the previous owner might have messed with the adjuster on the throttle cable near the carb. If this is too tight the throttle cutaway will not even touch the idle adjustment screw and the adjuster will have no affect.

 

It was surging up and down even when warm. When it comes down off of high idle, it will surge back up some. I cleaned the heck out of the carb and jets a dozen times and I think the problem is in the slow jet. I tried to clear that tiny thing out as much as possible with wire, boiled it, and put it in an ultrasonic cleaner. It is actually running pretty good (surges up just a little after it comes down) at the moment but the only problem comes when you crack the throttle hard wide open and it will die. My son can get on it without killing it but if you go all *****, it cuts off. Thanks.

 

Sure sounds like an air leak somewhere.

 

If you go with changing the choke, I replaced mine with a choke cable I bought at Advance auto parts. I drilled a hole in a convent spot in the plastic. The original lever had been damaged.