Hi Remi,
> I am following this thread from the beginning with interest. It is
> also my opinion that your problem is not caused by vapor lock. I do
> not think it is a fuel pressure problem either as lack of fuel makes
> the engine sputter, not just loosing power as you described.
Well, the fuel pressure dropped. I can't argue around that. I also
closely monitored the manifold pressure, but it didn't surge in any way.
> If your
> engine lost power while still running smoothly,
It didn't run exactly smoothly, it didn't sputter either, it was more a
rough running.
> To determine if this is the cause, I
> suggest you try to run the engine with the waste gate in a frozen
> position. Stabilize the aircraft at the Barcelonnette 4000 ft at full
> 115% power.
Good idea, although I'm not at Barcelonnette anymore. But I think I can
repeat the procedure while flying at altitude. (Problem at Barcelonnette
was that the brakes didn't hold full power and there wasn't anything to
attach the plane to, except for the runway parallel tie down steel cable
but it had some gliders attached to it as well. So experiments were
limited and I definitely didn't want to land in the Ubaye, which is fine
for rafting but not for landing.)
> Turn off the TCU switch. Then the waste gate will remain
> in a fixed position. Reduce power to idle. Increase power to 115% as
> you would do for taking off and see what happens.
Sounds like a good experiment. I thougth already that maybe the waste
gate is sticky, and while opening after reaching enough pressure, it
gives a tiny boost peak, too fast to show up on my manifold pressure
gauge, but enough to trigger the fuel pressure regulator.
I will also lock the prop in the max power setting, to rule that out
too. So, with the waste gate locked and the prop also locked it is
interesting to see what happens to my little problem.
Thanks,
Frans
|