ORIGINAL: bob27s
just to review this.....
do you see a rapid (within 30-60 seconds or so) elevation to the extra 2000 rpm, or does it slowly gain rpm through the run ??
If you throttle back to low/mid throttle..... hold it there for a minute, and then go back to full throttle..... does the engine jump to where it was, or does it drop in rpm and then starts the RPM climb again?
The one run it did ramp up 2000 rpm in about 30 seconds. Muffler nipple is clear and you can see bubbles flowing back into the tank so I know it's at least getting some pressure. You can blow through the pressure line into the muffler no problem. I'll have to do more testing. This engine has always performed like this. I'm wondering if it is an issue with the entire carb, but then why does it only show it's ugly face after about a half tank of fuel? By the way, this engine is an Italian one purchased in 1996. It had low hours due to this frustration with it so it sat. Recently it was freshened up with a new ring by Frank Bowman.
Mike