I would very much appreciate some help with a problem. I have a low mileage 2004 Arctic Cat 400 TBX that has become hard to start and idles poorly. I have a friend who is a pretty good shade tree mechanic and I told him I thought it sounded like a carburetor/fuel issue, and he agreed and said he would work on it for me; since I live out of state. So, I bought a new OEM carburetor, intake manifold (w/ a new gasket/o-ring) and new clamps and he cleaned and gapped the plug and installed the carb and manifold. He said it "helped a little' but didn't fix the problem. Next, he replaced the coil w/ high-tension wire, spark plug, spark plug cap and seal and the air filter. He said it was "better yet, but still is too hard to start." Before I bought a new magneto or CDI unit, I talked to a 4-wheeler mechanic via the phone and he said it almost certainly wasn't the magneto or CDI unit because it would run and it was getting good blue spark. He felt it may be a that the idle was turned up too high and caused the carburetor to lean out while the choke was on and we were starting it. I would greatly appreciate any help.

 

On any engine, the first thing to do is change the plug, while it is out you check compression, under 90psi, and you need to check valve clearances. If they are OK, you have worn rings or a valve seat problem, or a blown head gasket, and are going to have to take the head off. If compression is OK, you may have the Suzuki loose magnet syndrome, I only had one, an Eiger and it made a mess, as the loose magnet jammed between stator and flywheel, wrecking both, but others assure me that the magnet sometimes stays on the flywheel, just producing poor running. The only way is to take the cover off and find out. Be warned, on manual versions, gears, washers etc, fall out when you remove the cover, and you need a parts drawing or manual to work out how they go back in.

 

Between 2003 and 2006, I believe, the 400 Suzuki motors were prone to magnet failure on the flywheel. I know new improved flywheels are available from either AC or Suzuki. Still those were excellent motors otherwise. I had a 2002, model before the problem, it was a tough S.O.B. Merryman gave great advice!

 

Thanks merryman. You keep referring to Suzuki in your reply, did Suzuki make the engine for the 2004 Arctic Cat?

 

Thanks hydrex. You keep referring to Suzuki in your reply, did Suzuki make the engine for the 2004 Arctic Cat? Also, it sounds like it really may be the hole magneto assembly then.

 

Arctic Cat used Suzuki engines for quite a while. I checked with the parts book before answering, and your model looks to have the Eiger engine. Do the compression test first, it is more likely to be low compression than a loose magnet. If your stator checks out electronically, it should be OK, even if the flywheel has a loose magnet, provided the magnet hasn't hit anything.

 

Thanks for the advice merryman. I really do appreciate you taking the time to answer me. I will check the compression and go from there, if my shade tree mechanic doesn't have a compression gauge that fits, I may just have him take it in; as if it is a compression issue it will be a more involved fix. I know he already adjusted the valves, but if it is worn valve guides or ring wear, it likely is more than he is capable of doing.
-Kurt