Problem with 9.9 Johnson carb.

I've got a 1980 9.9 Johnson with a 15 hp. carb., that I had rebuilt last spring. It ran well the few times I ran it then, but I haven't run it much since. I tried to start it last week, and it wouldn't start. Finally got it started by running marine carb. cleaner through the motor, but now I have to keep the choke pulled out about half way for it to run at all. Does anyone have any ideas?

Sounds like you need the carb. cleaned again,the high speed jet might be dirty.

You cleaned it last year, but then didn't run it for a year. So, whatever gas you ran through it then probably has varnished, and gummed it up again. So, it is likely due for another cleaning, then more frequent running.

Magg. If you left any old fuel in the carb at all, as bass said it prob. varnished, then when you put new gas to it the varnish broke loose and pluged everything up. A good carb. cleaning should do the trick then when you store it this fall be shure to run most of the gas out then put some Stabill in and run it out, this will prevent the varnish buildup in the future. This is a very common thing among small engines of all types. You will find stabill works on all engine and fuel systems. I been usingit for years and sware by it.

I have seen the stabil work first hand. Trust me when I say I have no mechanical/motor/boat skills. I tried to fire up the pressure washer after letting it sit all winter. Stabil brought it to life.