2010 Polaris Sportsman HO Issues
Good morning guys,
Just registered here hoping to pick your brains as I am at my wits end with this thing. Little History, I am military and PCS'd overseas for 3 years. I left my ATV with my dad over that time and it just sat in his back yard and rotted. Fast forward three years, I come back and try to get it started and find all the rotted parts. Initially, I replaced the battery, external fuel lines, filter, petcock, oil change, and spark plug. Second step, I dissasembled, soaked, and cleaned the carb and all jets (with a jet pick) from the varnish that was inside of it from the fuel sitting for that long. Put it all back together and the ATV would idle great but would die as soon as I would throttle up. Upon closer inspection of the fuel, I opened the tank and the fuel sending unit was also covered in crystallized ethanol/gunk and the fuel hose had disentegrated in the tank (Idling on fumes I guess?) I cleaned the unit, replaced the hose, and reinstalled the unit back into the ATV. It was late so I came back to it in the morning to find the air box, crank case, and cylinder full of fuel and the fuel tank empty. I disassembled the carb again and found the float bowl wasn't fully stopping the flow and was causing to constantly drain. I adjusted that and now use the petcock every time I turn it off as well as changed the oil again to remove all the fuel.
Now the kicker, It has fuel flow and throttles up great but will no longer Idle. It is spitting out black from the exhaust and smoking at the collector where it connects to the engine. Just to start the ATV, I have to give it full throttle while while cranking the starter and then let off some but still applying fuel to keep it running (very rough and seems like it may be getting too much fuel now. I have tried two carbs (one chinese cheapo version just to see how it reacted) and it currently has the factory mikuna in it. Both units have the same exact symptoms, wont idle, starts at full throttle and will run with partial throttle but will die as soon as throttle is released.
Sorry for the novel but hopefully the details may help some of you experts! Note, I am a hobbyist and enjoy working and tinkering but am by far not an expert. This ATV has me pounding my head against the wall at this point and am hoping for a fresh mind. Also, I do have the service manual for it as well.