Bought 2 ‘04.5 SP400’s and am having problems with both bogging down climbing hills. Two friends with same models are having same trouble. Local dealer tried to richen up the carburetors but doesn’t help. The dealer called the Polaris hotline. They say they are starting to receive calls about this problem and they “think” the fuel pump is too small??? They are going to use by buddies as a guinea pig. Anybody else seen this problem? Pulled sparkplugs on both of mine and they were tan. Any ideas?

 

My sister-in-law is having the same problem with her 400, she just bought it a month and a half ago.

 

I'll post what we find out, let me know if she gets hers fixed before we do.

 

It's hard to believe that the pump would be too small to deliver the amount of fuel required to get you up a hill, these things aren't that hard on gas. One way to check would be to stop for a few seconds to let the float bowl refill, then try again. If it pulls strongly for a few seconds, then dies out again, it sounds like it IS starving for gas. If that is the case, it should get lean enough to backfire or miss, etc.

 

Chilly,

it is hard to believe it is the pump, they will do it on every hill and they do miss, but not backfire. we tried pulling the choke while climbing (not recomended as could cause driver to lose control!!!) to see if it would help if it was to lean and it makes no difference at all.

 

Will do, she's taking it back to the dealship within the next few weeks.

 

Same Problem here, I videotaped mine and have it at the dealer now as we speak (video taped it so someone couldnt say it runs fine) Mine will spin on a hill and then after a few seconds resort to a sputtering mess. Afterwards if I wait for a few seconds it will take of great for a few seconds and then again return to a sputtering mess. It bogged out bad riding up a couple of hills with my wife on it. Can we just swap a fuel pump off a 500 on it or something or are they same.
I was told My plug was black, just a minute ago on the phone, so he dropped the main one notch and we will see.

Ron

04 Sportsman 400

 

ktmguy70,

I was wondering the same thing about the 500 pump. Keep us posted on your progress.

 

Will do trailrider.. As I siad I video taped mine acting up as seemingly the dealer cant ever get it to act up. It seems to me that It only acts up on a hill and under a bind.
I can runn full throttle all day long and never run out of gas or have it bog, I have it clutched pretty cleanly with the kit I have in and can pull wheelies in high. If Im at the bottom of a steep bank and just nail the throttle and go up it, Im fine, if Im at the bottom of the steep bank and have to spin up it, it starts sputtering. I can let up on the gas for a second and Im fine again for another few seconds,so we shall see I suppose. My plug was VERY black.. so In theory dropping one May a notch on the main may solve the problem, if not im looking somewhere else.

ROn
04 Sportsman 400

 

My sister-in-law got her 400 back from the dealership. The dealership said they rejetted, and should be ok now. She's going to test it out in the next few weekends.