300EX Won't idle and won't run without choke??

[atv223]

I have a 2002 Honda 300EX. When I last put it away, it was running fine. Unfortunately, that was over 5 years ago and since I didn’t think it was going to sit for so long, I didn’t take any longer term storage precaution. Needless to say, I knew it wasn’t going to just start up.

I put a new battery and spark plug in it. Drained the gas take and put in fresh gas. I pulled the carburetor out and took it apart. I soaked all the jets in carb cleaner and then blew them out with compressed air. I sprayed the inside of the carb and all orifices with carb cleaner and with compressed air.

Once I got it all back together, I tried to start it. With the help of a bit of starting fluid it started. Problem is, I starts with the choke on but won’t idle. As long as I have the choke on and am giving it a little gas it runs. As soon as I turn the choke off it stalls. Even once it was warmed up, it wouldn’t start or run with the choke off.

Please help!

[atv223]

Here is a quick follow up. After leaving it sit overnight, I went out to try again. This time I just put the choke on and hit the start button. I wouldn't start until I gave it some throttle, then is started, running a bit rough. If I let off the gas, it stalled and I started it again. Then after letting it run a bit with some throttle, it started to run a bit better. I let off the throttle and surprise, it idled. Then I took the choke half off and it still ran and idled. Then I took the choke completely off and it idled and ran without backfiring. It would sit there and idle with no problem. If I shut it off, I barely had to hit the starter and it would happily start and idle.

My only theory is that one of the circuits hadn't been cleaned out well enough. As it say with some fuel in it, it loosened up and when I started it today it finished clearing it out!

I won't let this happen again. Got a battery tender and will drain the carb and use Stabil!!

[wilkin250r]

It sounds like you probably had a clogged idle circuit. The pilot jet is the one item most people think about, but it's not the ONLY part. The old gas probably turned to varnish in the idle fuel passage leading up into the carb.

Stabil may or may not prevent future problems. If your quad sits like that again, when you clean out the carb, be sure to spray cleaner through ALL the fuel passages, not just the main jet.

Clogs in the idle fuel passage are not uncommon, because they are extremely small (so they clog easily), and many people don't pay much attention to it when cleaning the carb.