97 Sportsman 500 starts and dies

[traktrjorj]

First Post: I just purchased a 1997 sportsman 500. The battery was shot when I bought it so I bought a new one and installed it. I turned the key on , flipped the choke switch on and punched the starter button. The engine started right up and ran for 15-20 seconds then quits. I emptied the fuel tank completely and dried it completely and drained the carb thinking maybe something was in the tank, carb or lines that was shutting the fuel off. Filled it back up with fresh fuel and punched the starter again. Same thing, it will run for 15-20 seconds and dies. If you try to start it up immediately, it won't start but if you wait a minute or so it will start again and die. Now if you do this a enough times sometimes it will keep running and seems to run pretty good but will backfire some if you let off the throttle real fast. The compression is great (100 plus) and I would bet it doesn't turn over more than twice and starts. I am thinking something is messed up in the carb but thought I'd get some of your opinions before I removed it. Thanks for any ideas.
PS: My brother -in-law had changed the fuel pump before he sold it to me so it's new.

[4getful2]

When you say flip the choke on,do you mean where the lever is sticking straight out? that first click is ,choke half on , clicked full the other way is choke ,full on.
Also you may want to inspect the amount of free-play in the choke cable ,down at the carburator, should be no more than 3/16-1/4" free-play and can be adjusted at the carb. on the end of the cable.
If that doesn't get it try disassembling the carb. and cleaning the pilot jet.

[traktrjorj]

OK will try that as I thought straight out was choke-on. Didn't realize there was a half on and full on. Will also check the free play. Thanks