Why won't it idle without choke?

Did you check the choke sometimes it
Gets stuck. Be cause if it's on it won't do anything it will die everytime you apply gas. Or the gas change over value on the side of gas tank I hit mine by mistake one time and it wouldn't
Go or do anything.

Have you checked the Crankcase seals? I have 2 Big Bosses with 250's. 1989 + 1992

Both were terrible at starting and idling....after much troubleshooting I finally changed the crankshaft seals. (Which btw looked fine from the outside!) machines can be Cold now and will start 2 or 3rd pull with the cord now. Idle perfectly.

Also the oil injection system stopped working intermittently. Machine would just quit.....crank and crank it forever. So I just started using 32/1 mix and unhooked the Oil Injection cable from the Throttle.

lever down to choke .pulls plunger up .

Full tune up and carb clean .get new plug,air filter.oil Chang ,carb clean and adjustment.that should do it.,., try fuel filters and test fuel pump see if it's functioning properly.,.

Hi Linda... Clogged carb jets and be a problem. Cleaning them is often very difficult due to the size of the orifice. sometimes welding tip cleaners or sewing needles may work. Forcing air is a good way but the acid test is to look into the orifice to verify you see light.

Another thought: Sometimes the fuel caps stops venting and the motor will act like its running out of power, rightfully so as it's running out of fuel. The vent in the fuel cap can be partially plugged or completely and the engine will act accordingly. Best way to test this is to remove the fuel line after the petcock(off/on valve) and watch that it flows fuel well. Also check the petcock filter to verify it's not clogged and check the fuel line to make sure it's not crimped.

You're problem doesn't sound electrical but I'd try to eliminate all fuel related problems first before moving to electrical as electrical trouble shooting can be a bear.

The air mixture adj screw sometimes has an "O" ring and sometimes not. Check with parts fiche for your model carb to know which.

Sounds like a passageway may still be clogged. I suggest that you try dipping it in carb solution for a couple of hours, then rinse and blow out everything.

It's starving for fuel.

well sounds like you need to clean air filter if that does not help i would go with your choke is sticking on if its a cable pull one make sure its pushing all the way back on carb check or if it is electronic one i would replace auto choke good luck

Hey Josh,
Cleaning a carb is a little more that most people realize..it takes someone with knowledge and training to really do one right... take it to a professional..

Sounds like the carb could use a cleaning and setting by a professional...install a new plug and a new air filter.. AFTER the professional carb cleaning and setting.,,do this and repost