Hey Guys... engine question;
The 109 hasn't been right since the 4th furrow Nick and I turned at Prophetstown. Here's a description of the symptom;
I open up the throttle, push the SR lever all the way forward, and run up the driveway (2% grade tops), and it goes like gangbusters for about 50 feet... then bogs just a little, and falls flat on it's face. If I'm quick to get the SR lever back, I can usually keep it from stalling, but from that point on, it's really hard to get it to develop any power.
If I shut it down, or let it idle for 20 seconds, it'll allow another 10 seconds of full power.
Note that under these conditions, I can usually run it to full goverend speed with no problems, just can't get any power out of it.
My suspicion was that I had some fuel-line blockage or a main-jet issue, but after giving it a cleaning-out and even trying another known-good carb, it still does it. Tried going to a cooler plug (suspecting detonation), fresh gas, and checked timing/gap... but no change.
It's a 15 year old 'service replacement' motor, and it uses a little oil, but not too bad...
Suggestions?