Originally Posted by
cmulder
Anyone here who has the current version and wants to try?
Instead of conncting the fuel line from the solenoid holder to the carb fuel nipple, connect it to the (empty
needle holder and put a plug on the fuel nipple.
Its a "quick and dirty" test and not suitable to fly (?) but will show if the idea works.
There is a major flaw in this idea: taking the HS needle out exposes the full diameter of the valveseat to the fuel flow, in other words ALL metering has to be done by the solenoid. That will result in such low values of the fuel curve that there is no more resolution to adjust....
The solenoid is merely an "on/off switch" for the fuel flow, but there still needs to be a tailored to the engine fuel restriction in order to make the system work. In Chris' design that is the 3D-printer nozzle that is selected to size.
In my set-up that is the HS needle, in the Stihl configuration there are restrictors in the carb, but if we take out the HS NVA and replace it with simply a solenoid, there is no such restriction.