I just rebuilt my carb on a 2001 sportsman and the idle mixer screw was set at 3 1/4 turns. I started it up and runs good but will not idle. 3 1/4 turns seems like to much. Maybe someone adjusted this before i cleaned the card. What should it be at??? And nothing seems to change if i turn this screw all the way in or out... And my fan stays on all the time...Is that normal???

 

If you're able to adjust the fuel/air mixture screw,someone has already removed the block off plug and tampered with the setting. Start at 2 turns out from a lightly seated position.Don't tighten this screw very much or you take the risk of breaking the needle tip and ruining the carb itself! You really need a carb adjuster tool or if you have small hands and a small screw driver,you can fine tune the idle while it's running.

 

I tried to adjust it while it was running but it didnt seem to change anything. Even with the screw all the way in, it still ran, and all the way out also

 

Possible then this fine tip of the adjuster was broken and stuck in the small hole in the carb. I've found several like this. You may want to take the carb back apart and see if this is the case. There is a small spring washer and o-ring you need to remove. You can tell by the adjuster tip if it's broken and also if you can't see through the hole. Items #31-34. Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse