Hi Karl,
We have been flying N135TD for two years, 250 hours, on MoGas (mostly). We
occasionally use AvGas when on trips, where MoGas is not available. We fly out
of Livermore, California, which is near sea level, with temps as high as 40 C.
We regularly fly over the Sierra Nevada mountain range at altitudes in excess of
13,000 feet, and fly in and out of fields 4,000 feet and above on days with
temps up to 40 C.
We have an XS with 912S, with the Europa standard fuel return mechanism. We
have had two problems we suspect are due to the volatility of MoGas, as follows:
1) We have had warm start problems we believe are caused by fuel boiling in the
carb float bowls. This is improved by shutting off our Skydrive carb heat before
taxiing back from landing (I strongly recommend carb heat for the 912S with XS
cowl), and by opening the coolant inspection door in the cowl after engine
shutdown.
2) We believe we have had vapor lock right after takeoff, only following a warm
start, and only in the winter time (more volatiles in the winter formulations of
MoGas?). The roughness goes away a lower throttle settings, and usually clears
out after a while. We may have that cured now with some additional fuel system
insulation under the cowl, but won't be sure until next winter.
regards,
Terry Seaver
KARL HEINDL wrote:
>
> I am sure this topic must have been covered to death, but I am again reading
> a PFA circular from
> 2001 which quotes that the tank temperature must not exceed 20 C, and the
> altitude must be
> below 6000 feet. Not much use for anyone flying in the Denver area.
> I don't want to use Avgas because it just opens up another can of worms and
> is a lot more
> expensive. My engine is 912S.
>
> Any comments, anyone ?
>
> Cheers, Karl
|