2002 Artic Cat 375 auto 4x4 Need some help.

[Rick Robinson 0]

My Arctic Cat ATV started sputtering and backfiring and losing power on acceleration and sometimes die. It idles perfectly. I thought it may be the carburetor float sticking and would knock on the bowl and it would run great again for a while. It then started doing the same thing but I began hearing a loud knocking like low octane knock. This is intermittent and does not knock all the time. Thinking it was the carburetor float and possibly an obstruction in the jets I cleaned the tank and carburetor and put a new kit in. Still had the same problem. Bought a new OEM carburetor It still has the same problem at any adjustment? It also seems to improve a small amount when carburetor is disconnected from the filter system. I am starting to think it may be something else causing this possible a Coil or electrical? I would appreciate an experienced reply. I do have automotive shade tree experiences but this has me scratching my head. Thanks in advance!

[Frank Angerano 825]

Welcome to Quadcrazy @Rick Robinson  

its a pain in the ass but I would check your flywheel.  There have been problems with the magnets coming loose and spinning inside the flywheel. The epoxy that holds the magnets fails and they slide out of position causing the symptoms your having. 
 

[mikeexplorer 224]

The flywheel magnet problem was common on years 2005-2007 models. He did not post the year of his machine. My first quad was a 2007 Arctic Cat and I did not have the problem. Guess I lucked out.  It is something he needs to check as it can cause his symptoms.

 

Mike

 

[Frank Angerano 825]

I seen that with not posting the year.

 I'm the last one to go into an engine without checking all the basic non invasive problems first and would continue to do so. Use this as a last resort if he gets nowhere with the other stuff.   

But if it is this problem and one of the magnets comes out.... oh boy. 
Also pulling that cover off is not so bad anyway.  
  

Edited February 25 by Frank Angerano

[quadnut20 75]

21 hours ago, Rick Robinson said:

My Arctic Cat ATV started sputtering and backfiring and losing power on acceleration and sometimes die. It idles perfectly. I thought it may be the carburetor float sticking and would knock on the bowl and it would run great again for a while. It then started doing the same thing but I began hearing a loud knocking like low octane knock. This is intermittent and does not knock all the time. Thinking it was the carburetor float and possibly an obstruction in the jets I cleaned the tank and carburetor and put a new kit in. Still had the same problem. Bought a new OEM carburetor It still has the same problem at any adjustment? It also seems to improve a small amount when carburetor is disconnected from the filter system. I am starting to think it may be something else causing this possible a Coil or electrical? I would appreciate an experienced reply. I do have automotive shade tree experiences but this has me scratching my head. Thanks in advance!

Welcome to QC !!