I have a 99 Xploerer 4x4 and after i get a the engine warmed up and under stress the motor losses all power. i've taken it to my local dealer and he said he fixed the prob, but he didn't. i'm thinking it could be a ring sticking, or on the other end of it , possibly the Coil. i'm not sure, but if anyone has heard of this before or has another suggestion let me know please.

 

welcome to the fourm. what the dealer do to fix it? is this a 300 or 400? did you do a compression test on the engine, this is the first thing i would recommend doing so you know it isnt the rings causing the problems. when you say loose power is it skipping, bogging, what are the systoms its doing?

 

opps it s a 400 Xplorer , i should have given you a better discript. of the problem. the Dealer changed the CDI and did a so called complete tune up. but after i went for a ride and put the bike under some load, Bang, the probelm wasn't fixed! and my dealer had no clue what the problem was. i'm not about to let him do a search for the problem, his shop rate is to high, and he can't guarantee he'll fix the problem.

i've done a compression test after letting the machine warm up and, to describe the problem, well the best description is that it sounds like a bogged out chain saw! i can hold the throttle to the bar and the bike won't move! it doesn't stall. it just starts to bog out and sputter. i've gone through most of the bike myself, filters , carb job, clutch re-build, and still no luck. i love the bike, its got some good power and gets me though alot when its running at peak.


thanks

 

you should be doing the compression test w/ the bike stone cold and w/ the throttle wide open for a few seconda to get an a good reading. i know some people have had problems w/ their counterbalancers but dont know if thats your probelm or not.sounds like a carb issue but you said you went thru it.

 

Did you check the bolt head on the bottom of the carb for wear? I just found mine on the same machine had a hole worn through it and leaking fuel .J B welded it, works fine now.It had similar symptoms.

 

had the same problem with my 400xplr. drove me nuts. it would run fine until you nailed the gas and then it would blubber,is that a word? anyway i finally fixed it by loosening the choke where it goes into the carb a couple turns. also check your vents on the carb.

hope this helps

 

I have an 01 Xplorer with the exact same problem. Runs great until I put a lot of load on it (Deep Mup, Really Steep Hill). Last time it happened I pulled my seat off (while it was bogging) and then yanked the top off the air box. Power was restored immediatley. I just changed to a foam air filter last night and added some air vents to the air box last night in preparation for a ride coming up. It looks to me like the machine just isn't getting enough air but I've had a Polaris Mechanic say he thinks that opening up the air box is probably just a band aid that will cover up another issue. I'm willing to try anything at this point (will be checking the fixes previously listed in this post) so if anyone has any more ideas I'd love to hear them. I've been battling this for 3 years and no one seems to be able to figure it out.
Good luck with your machine. I'll let you know how mine runs with the air box mod and new filter when I get back from riding (weekend of the 28th this month.)

 

putting holes in the air box just invites water and mud in there i would think. is all the vent hoses all clear and not pinched. air filter not plugged. i know rick has said that the vibration on the bike makes the fuel foam up and there for starve it for gas.

 

I took the machine out for a ride last night with the new foam filer and vents in the air box. I also adjusted the choke a few turns out of the carb (bolt on the bottom of the carb is starting to wear but it's tight and no holes). It definately has more power now than before, I could almost stand it right up from the start. My question now is..... When adjusting the choke cable at the carb.... Is turning the screw out "loosening" the choke cable or tightening it? I'm wondering if the choke was always slightly on and thats why I would lose power under heavy load? If that is the case does that make sense with me getting power back when I opened the air box? With adjusting the choke do I need to worry about the machine running lean or anything like that? Thanks for the help.

 

I had the machine out this weekend and put it to the test. Between adjusting the choke cable out a little and the modifications to the airbox (new UNI foam filter also) it now runs like a bat outta hell. More power than ever and I couldn't get it to bog down for anything. Put it in deep Mud and water and all went well. I honestly believe that the airbox on this machine is very poorly designed. I added six 1" air vents with prefilters to the actual air box itself, drilled a 1' hole in the top of the snorkel/neck (the stock one opens against the gas tank and I think that causes an issue with steam). We were riding in 70/75 degree weather and I never got a temp light and the plug looked good so I don't think it leaned it out too much. This looks like a cheap/easy fix for a common problem. First time in three years I've come home from a riding trip and didn't have to try to figure out what the heck was wrong.