Hi Obxwes,

Thanks for letting us know, we really appreciate the feedback. I expect we will be getting more feedback as the season progresses.

Once we isolated to a fuel feed, we were having a hard time identifying if the muffler pressure was the problem, or adding extra muffler pressure just forced more fuel and just hid the problem. From the feedback we are getting, it appears the carburettor has a fuel draw problem and it can be fixed by drilling out the fuel intake nipple and drilling a hole in line with the brass insert to line up with the intake nipple.

I purchased a new GMS.47 last week and again the brass insert hole is not aligned, it is off center towards the direction of the needle valve, away from the carburettor throat.

I'm going to drill both he intake nipple and the brass insert before breaking in.

Just as a reference, I also noted the following while the engine was new:
1. The gap between the low speed needle and the carb brass insert in the throat of the carburettor is 23 thousands when wide open.
2. Hi speed needle adjustment was: 3 3/4 backed out (from tightening the needle in until it just stops)
3. The lows speed needle was backed out 1 7/8 turns when the throttle was completely closed.

in the future, this may be a good starting point when working with a carb that is way out of adjustment.

After I break the engine in, and adjusting the carb, it will be interesting to see how much of a change there is and if it will be closer to the final adjustments I posted earlier in this thread.

Again, thanks for the feedback, I'm looking forward to more results from others.

Fly4Fun,

Wayne Miller