I have a 2001 Xplorer 400 with few hours on it. It is cold up here lately and my throttle is always froze for the first couple minutes. Also, it takes a long time to warm up before it will idle on it's own. It even backfired a couple times when I am driving it and it is not warm yet. It seems to idle high till it warms up, and it is hard to get it in gear. Do I need to put in a heated place to let it dry out or what? Do you guys have any ideas? The power is excellent, so I don't think there is any real big problems. Any help i s appreciated.
Thanks

 

You have encountered the "typical 400 frozen throttle syndrome" You have condensation which is freezing in the throttle and or the oil control line. The freezing normally takes place at or below the junction of the control lines.

The backfiring that you are experiencing is the ETS control doing its job, because your throttle is sticking.

Your Polaris will be hard to shift into gear if the idle is too high. But it would be hard to tell where the idle should be if the throttle is sticking.

The quick fix is to aim the better half's hairdryer at the cable junction and the lower half of the oil control line. ( This may not go over too well at your house)

Lasting fix: take the cover off of the oil pump on the engine and clean out all dirt, crud and frost. Take the cover off of the Emergency throttle switch and check for moisture in there. Douse it with WD 40.

Try and put Polaris cable lube in the throttle cable after drying it out with the hair dryer.

In an emergency or if you are in a real hurry you can pour a pan or bottle of hot water over the cable to get you started.

If the 400 does not want to idle properly when cold, very carefully adjust the choke settings so that it runs smoothly at 1/2 choke when the engine is cold.

Too much choke adjustment will drop your fuel mileage by 1/3 if you are not careful.

The airscrew on the side of the carb may also need tweaking counterclockwise to make it a little richer.

Always, always carry an extra spark plug or two with you in the winter. If you have made your adjustments too rich the plug will fail without warning, just like somebody flipped a switch.

A properly adjusted 2 stroke Polaris 400 will be able to sit outside in the winter for over a month with out being run and start instantly when required. By next spring you will be an expert on cold weather two stroke carburetion.

There are tips for tuning in your owners manual but they are only a baseline and your results will vary.


"I love the smell of two stroke in the morning."

 

Good reply Thor. I have also been a victim of my throttle freezing and also the battery. Nothing sucks worse than having to keep pulling the recoil to get it started when it's about 5 degrees outside. Once it warms up for about 5 minutes or so, the throttle thaws out and everything is fine. I have learned that you have to keep the rpm's up to keep the battery charged. I leave my bike running all the time when i stop. It actually seems like it runs better in the extreme cold. You just have to let it warm up for a while. Well anyway I just wanted give you a big pat on the back for the good post Thor.

 

You said it just like it is, Thor.

 

THOR,
Your post was great,however,I did read one minor mistake.You said to turn the air screw counter clockwise to richen it,that is incorrect.

TO richen the mixture on a the Xplorer's carb you have to turn the airscrew clockwise.To lean it,you turn the air screw counter clockwise.
Bill

 

Thanks guys(Thor)! I had it in the garage a couple days ago with the heat on for awhile. Left it in the cold for a couple days. Now today, started it and it ran fine. It was great riding in the woods today. There was about 8" of just pure fluffy snow. In some spots it came flying up over the machine. It was great! I think I'll just keep my snowmobile in hybernation or maybe sell it to pay off the wheeler. The wheeler is much more fun with less than a foot of snow, which is what we have gotten in the last couple years here in MN.
Have fun and thanks again!

 

My TBlazer runs fine in cold weather, but to make it shift easier while its idling high(before being completely warmed up), I pull the choke half shut to bog the motor, slap it in gear, tap the throttle to keep it running, then off I go