18-04-2025, 09:31 PM
Hi
Fixed jet carbs like the Zenith are quite sensitive to float bowl fuel level. Too high and it will tend to be be over-rich, and even "siphon" out with the engine stopped, especially when hot. Too low and it will be weak at low airflow, giving a flat spot between idle and full power. At one time, replacement needle valves were supplied with a selection of different thickness washers, to allow the level to be tweaked.
I suspect your float bowl change has altered the fuel level for the better.
Fixed jet carbs like the Zenith are quite sensitive to float bowl fuel level. Too high and it will tend to be be over-rich, and even "siphon" out with the engine stopped, especially when hot. Too low and it will be weak at low airflow, giving a flat spot between idle and full power. At one time, replacement needle valves were supplied with a selection of different thickness washers, to allow the level to be tweaked.
I suspect your float bowl change has altered the fuel level for the better.