I wonder if there is a clog somewhere internally, causing a lean condition on the low side. So no adjustment will allow enough fuel to pass through to fix the issue. I wonder if something like an ultrasonic cleaner would work.

The only difference between the DLE20 and 30 carbs are the size of the venturi, right? Since we can simply lean it out with the adjustment screws, seems like a good upgrade. Maybe the larger venturi will lessen the chance of getting it clogged up?

By the way, anyone know the part number for the Walbro carb for the DLE20? Just for future reference, if needed.

Thanks