I have a 2000 Kodiak 400 Automatic that is giving me fits. It won't start but will every now and then backfire when you are turning it over. I took the carb all apart and cleaned it out and it all looks brand new and appears to be working just fine. I have good spark and even if I put fuel into the spark plug hole and try to start it it still does not fire. It is also has become very hard to pull start and when you try to pull start it it feels like something is either hanging up in the motor or something cause it has an abnormally loud sound when the motor turns over. Any help would be great. I also took crankcase cover off and everything looks brand new inside so I'm not sure where to go from here.

 

Looks can be decieving. You need to take that to a dealer or a classified mechanic

 

first take out the air filter and liik for fuel in the air box it may be flooding and backing up into the airbox...also check the overflow hose to see if it is plugged...

 

Is this a new problem or an old problem?

If this problem is new, do you run an automatic cam chain tensioner on your bike? Most quad motors are fairly close to bike motors, considering they are both OHV (Jap bike motors that is). If have an automatic cam chain tensioner, your cam chain may have actually jumped, I've had that problem occur to me. After that, start with your plug, if your back firing, it's a sign of too much fuel, not too little. You could in theory backfire from too little, I would suggest you make sure your fuel system is ok. Your cam chain tensioner type will be in your service manual. Next, if you see a good spark while doing an "air" test, you may actually not be getting proper spark when it is under load. Replace your plug, I would start there. If your pulling hard, it definately sounds like a plug problem to me. The abnormally loud sound, what does that sound like to you? What you could be hearing is fuel not lighting completly inside the cylinder and it'll sound quite strange. I would next do a timing check on your motor, your timing could be effed up. Check your cam timing and valve clearences, you may need to shim your valves (it's an easy process, I can tell you how to do it). You probably have a CDI, you may have a fried CDI, but I would do all the other things I suggested first and see how it works, it sounds like a timing/cam timing issue, or perhaps a bit of valve clearence. Check the Timing first, cam timing requires you to remove your tank or motor and pull your heads and check it, which is not super easy.

If it's not new or has been doing it since you got it, I'd check your jet size, you may be too large for it.

Hope that helps, I'm a bit of a scatter brain right now.

 

Thanks that info is kind of where I was headed just wondering if I was headed the right way or not. It is a very new problem. We had been riding that night and everything was fine and my wife was on it, she pulled up to our campsite and it hasn't hit a lick since. The plug is new and has excellent spark in an air test. I completely rebuilt the carb already so I know it has to have good fuel flow, or you would think so. The quad has never ever been to a shop for any sevice. So valve clearance I would say could be an issue. I purchased it new in 1999 and other than often oil changes a fan motor and a water pump it has been the best most reliable quad I have ever seen. Has over 13,000 hard miles on it. Still looks brand new, and would recommend to anyone.