I purchased my new AC 250 back in October and have been very satisfied. However I have noticed as it has gotten colder that it doesn't like to run until it is warmed up. And last night I wanted to take it out and play in the snow, it was about 12 degrees out. It started fine and I let it idle for about 10 min. Then I tried to take it out. It just spit and sputtered around and it would backfire. especially when in a pull. It did improve some with time, but even after running for about a half an hour when I would take it out the lane and get into fourth and fifth gear on open throttle and it would spit and sputter and backfire. I could play with the choke to get it to run a little better, but you shouldn't have to keep working the choke on it. Does any one have any idea? Will the backfiring hurt anything in the carb?

 

I had the same problem with my 250, try some gas line antifreeze.

 

i have a 2001 ac500 it is a bear to start when it is cold out,doesn't idle, realy gets me bummed. it only has 250 miles on it,tonight i put some iso heet in the tank, i let it run for 10 minutes and it started idling like it should,we'll see how it runs after sitting over night.a friend of mine burns gasohol in his and he doesn't have any problems.i also noticed ice crystals forming around the gas cap,not a good sign!

 

Mine is kinda cold natured too. I hauled min about 50 miles two weeks ago in 25 degree weather. When I arrived, I did not want to start unless I gave it full choke. It then did not want to idle, would rev up like it was leaning out with the choke on. Could very well have been gas line freeze, because all the other guys had trouble getting their quads started as well.(All different brands, I had the only arctic cat.)

I'll try the gas antifreeze to see how it acts.

Anyone else got the 250 4x4? If so, what do you think?


Jason

 

well all i know is that it doesn't get near that cold down here in texas but last weekend it got down to a frigid 29 degrees and my ac (purchased new this month) died out after "warming" up for 30 minutes. i was at the dealer today to see if he ordered my brain bucket and i was looking through an ac catalog when i saw an engine block heater. you might talk to your dealer to see if you can get one of these. i don't know the price but i'm sure it would be worth it.

 

I dont have a AC 250 but i do have an AC 300. I live in alaska and have rode my AC when it has been stupid cold. It hasnt given me any trouble at all and i keep it under a tarp outside. I think it is a little water in the gas. The last time i got some gas it ran a little rough and i put some gas line anti freeze in and it solved my problem. Any way it cant hurt to try Good luck.

RAC

 

It sounds to me like you guys need to go one main jet size up to counter act the leaning out the cold weather has on your ATV's.

 

Boner, I thought that the cold created the opposite problem in the cold. I was thinking that the mixture would be to rich. I have noticed that mine does not take the throttle as well when the air temp falls really low. I thought it was a rich condition.

Cheers Jim

 

Hello all, Well I put some heet antifreeze in last night to see if that helped. It was about 10 degrees out. I also warmed the bike up in the garage with a space heater to make sure no fuel lines were froze and the carb was nice and warm. It ran and idled fine in the garage, so I took it out. Still the same problem, get to about third or fourth gear on the open road and it starts cutting out and backfiring. So I don't think it is a problem with freezing. I am thinking that the spark plug may not be hot enough to ignite that colder air fast enough at higher rpm in a pull. Does that sound like it could be it? I have seen a few other posts to the like.

As for the carb being to rich or too lean, guys that makes since, but this bike is only 3 months old and I hate to think I need to go tuning around on the carb. I am going to contact the dealer and see if anyone else has had this problem. Don't get me wrong, I love my AC. But from the number of posts already, I think this is a pretty common problem, and I would bet that I aint the only one a little upset after buying a new bike and then not being able to ride it in the snow. I'll let you know what the dealer says. Hoping to get this 'cat running by xmas.

 

My 500 started doing that this fall. It runs fine in 2nd with the throttle pinned(when you are really pulling it) as soon as you are on the road and shift into 3rd or 4th and lug it, it will backfire and miss. It wasn't cold enough to freeze the gaslines or ice the carb. I drained the gas(in case of water) and put in fresh stuff, still runs the same. I think there might be some crap in the carb, I think it is running lean, (causing it to miss) plug is really light colored not its normal color. Haven't had time to work on it lately maybe get it tackled this weekend. Let you know if I get it fixed or find out anything. Aczr2k