Hi everyone, I am new to the forum and a new ATV rider. I purchased a 2003 Sportsman 700 last year and it has done me great through the winter and for the first part of the summer. However, just today I had problems with the idle. The ATV would start fine but if I did not keep my thumb on the throttle it would cut out. I let it warm up but still the same result. I then took it down the road to give it a run and it backfired on me a couple of times, which it has never done before. The backfire seemed to take place when I reduced my throttle. Anyone have any ideas what might be the problem and where would best be to start to correct this issue?

 

it sounds like its running lean/rich which is a sign of backfiring. check the rubber boot between the carb and the intake to make sure its not cracked. also make sure the air filter is clean and not off. check all vent lines to make sure no restrictions like plugged or crimped for starters. welcome to the forum.

 

Okay, stendori. I will let you know what I find out. Thanks.

 

Take carb cleaner and spray around the intake boot while its running, if it speeds the motor up , the boot is cracked, if the boots ok then the pilot jet in the carb is probably plugged.

 

The 02 & 03 SP 700's were factory set very lean at idle. They needed to do that to pass emissions standards. There was even an "unofficial" fix-it memo from Polaris to their mechanics. They were having lots of 700's come back with this problem. Mine did the same thing. It would run better at 1/2 choke then it did with no choke. I installed a DyoJet jet kit on mine. Worth every penny!!


Another possible fix: There is a throttle cable adjustment. Maybe the thottle cable stretched just enough to not let it dle. Find the throttle body and cable. There is a rubber sleeve about 5 inches down the throttle cable. Pull the sleeve apart and adjust the idle by turning the nut.

 

I have an 02 700 and had similar problems and it turned out to be the exhaust donut,it caused a lean condition,
As a matter of fact the exhaust manifold was cracked and distorted,it puched so many donuts the cops were going hungry.
The 700 manifold was so expensive i replaced it with an 800 header ,easy repalcement and runs better,sounds great too.
Hope this helps, post back if this is your problem too.

Lou

 

Ditto, same here. I now have the dual header pipe too.

Also check the airbox snorkle didnt suck in the foam around it or the gas tank vent.

The front exhaust donut (NAPA part # 31360) at the Y-pipe exhaust manifold wears and may leak.

I have replaced the carb boot/adaptor (p/n 1253415), the rubber gets weathered/dry rotted bad on some and may crack through.


Also ...
the water pump cover should be a metal replacement of the leaky original plastic cover on '02-03 models.
This was a Tech Service Bulletin for models in '02 and some early '03's.

The crank breather filter should be omitted for colder climates, this was also a Tech Service Bulletin (TSB). It added an insulated hose (w/1" slot).
The TSB is #S-03-05 and the part # is 2202744

Also some machines, mostly '03's have cold weather start jetting updates, both of the TSB's and the jetting should have been taken care of under warranty.

Jim