We had this atv since 1998 and the last time we had it serviced was in about 2001 so we've been running it about 150 hours without oil change..etc... so i started it up to ride it in the snow about a month ago and it was backfiring when i pressed on the throttle a little bit. I dont know what causes this problem. I thought that it might be cold and the jetting or w/e is off. But i started it up today and it still is backfiring when i revv it up above idle. The pipe and everything is all kinda rusty and dirty but i dont think that should be a problem should it? if somone is famillair with this atv can u help me please.. thanks in advance -Cruz-

 

4 stroke ATV's are all basically the same. My bro has one of those anyway.

Leaky exhaust contributes toward backfiring. This kind of backfiring only accurs at decel.
Lean idle contributes to backfiring, but only at decel.

Bad plugs and plug wires can cause backfing under throttle.
Valve adjustment too tight might cause backfiring.
Mixture too rich can do that. Slides stuck or air filter clogged can do that.
Mixture too lean can cause popping inside the airbox. MAke sure that you are sure that you know it is backfiring or if it is intake poping. If it is lean, check float bowl level, filter screen, main jet (clean), slide spring, maybe even need to clean the whole carb.

I believe your problem is plugs or carb or filter. You should be able to fix it easy.

The normal combustion process creates acid in the oil. Not changing the oil often enough is like pouring sulfuric acid into the crankcase. Even if you get it running great when you fix this problem, this engine wont last nearly as long as one that had it's oil changed on schedule.

 

okay thanks dude!!!! i just bought oil so im going to change it tomorrow morning but how do i go about cleaning the carbs? I looked at it and im going to have to take off the plastics to get in there. so when i get to the actuall carbs how do i cleat it? adjust the jets? etc...

 

For the most part you can just use carb cleaner spray to remove any gum or varnish you see in the carb. The jets are the little brass metering orifices that control the fuel mixture. Just look at them for scum.

If the slide is sticky (assuming the slide is a vacuum one) you could try removing it and cleaning it, or maybe spray silicone on it.

My website has tips for adjusting the idle mixture on a 650. The 400 is the same procedure except only one carb (easier).

The slide diaphram can't have a split. The carb hoses can't have splits or be loose. The float in the float bowl can't have varnish stuck to it.

Change that spark plug first. Never use Champion plugs.

 

man i got one and have had the same problems before, and it only happens when i have about a quarter of a tank of gas in it, so i switch it to reserve and it will run fine, not sure why it does it but i find that it does not like to run unless it has more than a quarter of a tank of gas in it. The quarter tank is via inside the tank not the guauge. the guage is way off.

 

also make sure the choke is not stuck, like actual cable

 

Haha i remember making this post about a year ago somtime around now.. .. so its a 1 year reunion.. WOoHooo..


We ended up selling the Prarie but i still got the other one.. with the same problem backfiring! haha i dont think it has been started since this post was made. I never found the use of having it so i guess thats why!. Im going to get it out of the shed and sell it soon so im going to change the oil and plugs and hopefully it will start!

Thanks to all you guys the past year!

 

All you guys.. i havn't posted in this topic in a while.. and i figured this is easy.

What kind of oil can i use in the kawasaki prarie?

Will yamaha Raptor 660 oil work??

 

Not sure about the 660 oil, but I just use full synethic oil in mine and it works just fine. I would say that the 660 oil would work bc the oil that each of the ATV makers sell with their name is just full synethic oil with there name on it and that is a quote from a mechanic at a dealership.