I use the original Spanish fuel filter/gascolator/drain/valve. The control has 3 positions:
- Take-off, landing, normal flight (gravity feed) at the front
- Aerobatic flight (flop tube) in the middle
- Closed at the rear
It happened that the original fuel control which I got from Spain would not lock positively: the main issue being that when I intended to move it from the normal to the aerobatic position it was almost impossible to lock the control in the middle position. It systematically went from the normal (front) to the closed (rear) position, missing the targeted middle position. I then had to fight with the control with both hands to make it lock in the requested position.
That was very uncomfortable, and unsafe.
I replaced the worn locking notches by a piece of tube with a bayonet-shaped groove to guide the rod locking screw and used the spring so that:
- The control rod is forced by the spring in the front half of the bayonet (front: normal, and middle: aerobatic). The control lever is almost vertical, downwards
- To move the control from the aerobatic to the closed position I must force the lever up against the spring until horizontal and then only I can pull it to the closed position in the rear half of the bayonet.
The fuel selection is now very neat and easy: push-pull between both open positions, but force up then pull to reach the closed position. One hand is always enough. Moreover, the horizontal lever in the closed position becomes an obstacle which makes my engine start swich difficult to reach: maybe one day it will prevent me from starting the engine with a closed fuel circuit...
Hope this can help...
Gilles
