On Fri, 19 Mar 2010 18:26:07 -0700, deuce wrote:

I have a Honda EB3000C generator with a Honda GX200 motor. It's only
a couple of years old and has very low hours. I decided to drain the
fuel and refill with fresh fuel. It had sat for about a year. It
wouldn't start at first but I sprayed a shot of Gumout into the carb
bore and it started on the next pull. So I let it run for about 10
minutes and it ran beautifully. I decided to drain the carb so I
siphoned out must of the fuel in the tank, restarted the motor and
shut the fuel supply valve off. It ran for about three additional
minutes but instead of stumbling and dying like I expected it started
to backfire very loudly so I quickly turned it off. I thought maybe
some water had gotten into the fuel so I drained the sediment cup and
the carb bowl. I put some fresh fuel in the tank and tried to restart
it. It would start and run maybe 2 seconds, then backfire and die.
Thinking there still may be some water in the carb I redrained the
sediment cup and the carb bowl and tried to restart. Same thing, run,
backfire and die. I added a little Heet to the fuel, repeat drain and
restart - same thing. I'm thinking the original backfire episode may
have damaged something but before I tear into it further I thought I'd
solicit any experience anyone might have with a similar problem.
Thanks in advance.

1.) Loosen the fuel tank cap a turn or so

or

2.) Remove the air filter

Will it then run?

3.) Pull the spark plug out and check for fouling

Clean the plug with a wire brush, emery cloth....

Will it then run?

Simple things first. Even check for a stuck choke.