Two questions:
- Do the top covers of the Webers have the PMO anti-percolation holes?
- When making the stop from high speed are you suffering the problem when using brakes to decelerate or are you compression braking and seeing the problem?
Float levels need to be set correctly since they determine (along with other variables) when the main circuit is activated. A 0.010" thick shim will move the float level by about 2mm which is the tolerance band for this adjustment.