I'm all confused with this thing. I haven't rode it in several months but the last time my son had it out, he let it rest for a while when he was on the Polaris. He went to ride the AC400 again and it would start and idle, but when you tried to give it gas, it spit, coughed and cut-off! We were done so we loaded-up. I have a tilt bed trailer so it would not climb on the deck with just an idle speed. ** Here's where it starts to get weird!** I hit the winch button to winch it on the trailer and I noticed a definite improvement in the idle. sure enough, it would throttle-up fine with the winch button pressed. Tonight, I went out and diconnected the winch wiring thinking, maybe a short, and cranked the AC400 up. It was doing the same thing..spitting, sputtering. THEN I flipped the ignitiion switch to the headlight position and the idle improved but this time it still wouldn't run (Just spit, cough, cut-off). I can't tell if it sounds like it's not getting gas or not getting air or an electrical short but somthings not working here! I don't understand the connection between the electrical system and running better (or rough) with headlights on/winch button pressed whatever???

Sorry for the long post but I need it for Relay for Life this weekend (clean-up afterwards) and any help is appreciated!

I DON'T KNOW IF THIS IS RELEVANT OR NOT BUT THE BATTERY IN THE AC400 IS DEFINITELY TOAST. WILL NOT TAKE A CHARGE. THE CHARGER WILL NOT EVEN COME ON WHEN HOOKED UP TO THIS BATTERY. THE CHARGER IS FINE ON THE POLARIS?

 

If it sit up that long without treating the fuel it could've gone bad , with the qualiy of the pump fuel we get these day's without treating it and let any quad now day's it can go bad fast , especially the small amount that a quad hold's !

The gas in the carb goes bad faster and will really gum up a carb , i always add some Sea Foam in all my fuel , in all my vehicle's even my car's and truck's ; i would drain the old fuel from the tank and carb and mix up some gas with the Sea Foam !

Sea Foam can be fould at all Auto Parts Store's and Walmart , the Auto Parts Stores get $6.99 + Tax and WalMart has it for $5.66 + Tax i just bought a can at my local WalMart Tuesday ; there's complete mixing instruction's on the can and it's the best fuel treatment i've ever used in over 20 yrs in Small Engine Service And Repair !

I highly reccomend this product because it does what it claim's to do , it also come's in a spray can called Deep Creep ; and it's the same as the Sea Foam and good luck with the quad !..........

 

is the choke on?

 

The choke is not on and I don't think it's bad fuel because I use a fuel stabilizer. Back during the hunting season when it was run almost everyday, it would do the same thing when it was first cranked-up. After about 6-8 aggrevating minutes, it would clear-up and run fine. Now it won't do anyting but idle. I thought carb in the begining. Afterall, Im an old moto-crosser and the 2-strokes are the worst in the world. I'm gonna pull the carb off tonight and clean-it out just to satisfy my curiousity. The one thing that still gets me is why does the idle improve when I turn the ignition switch to the "headlight on" position? It also had a better idle (an actually ran) before when I would depress the winch button. It just has a definite better idle now, but not running with the switch full-on or winch button pressed.

 

I remember reading a few posts on here of someone whose machine ran rough and when they hit the winch button or turned on the lights it ran fine. I believe their particular problem was something to do with the charging system. The magneto or something like that.

Something was craked on the windings on the magneto. So if you don't find anything in the carb do a search on here for Magneto and you should find it. I don't recall how they diagnosed it or fixed it.

SJ

 

I'm glad to hear that it may have happened to someone else. I thought I was losing my mind!

 

Sassee,

Only thing that pops into my mind now that I re-read your initial post is the Battery being TOAST and the engine running better with the lights on or while hitting the winch button has me leaning toward your Voltage regulator.

If it puts out too much juice it can overcharge the battery and fry it along with other expensive charging system components. Your charging system should be controlled by engine RPM's. It kicks in at higher rpm's.

Funny part is creating more drain (turning on the lights, hittign the winch switch) on the charging system gives you the correct amount of juice to smooth the engine out? Still sounds like the voltage regulator.

There is a test in the service manual for the charging system and the voltage regulator.

SJ

 

I have a manual that i downloaded from Arctic Cat and I think there some test procedures in it. I will try to get to it Saturday afternoon. i was going to use the AC at our Cancer Society Relay for Life event Friday night but i guess i'll use the Polaris instead. do you happen to know what the correct voltage should be at idle spees? I can walk to the shop and check it really quick. (The manual is on my computer at the office)

 

I believe with the engine runnig at a high rpm (5000rpms) with a volt meter connected to the battery terminals your volt meter should read between 12 and 15 volts DC. This is listed in the electrical section (section 4 or 5) of the service manual.

There is another test for the juice before it gets to the volteage regulator/rectifier. It is fairly easy but I don't recall which connection have to be made at the plug where the wires comes out of the engine off the magneto. I know the voltage should be 60 volts AC but I amnot sure what connection you need to make to test it but here again the engine needs to be about 5000rpm. Revved up really high. Where you need to connect the test wires to do this test is in the service manual.

SJ

 

Thanks!

I downloaded the manual to my jump drive and will take it home with me. i'll work on it saturday afternon.