I went  up today for a few laps at 3000 over Paine Field. The engine ran
well
below the staging point, but started stumbling when above the staging
point. It
ran smoothly through the staging transition on the ground, but  when in the
air I
could not tell by the mixture monitor if it was lean or  rich. I tried
leaning it
out and richening it up, but results were  inconclusive so I stayed below
the
staging point for the remainder of the  flight. I'll tune it in flight when
I can
get higher.  Temps were  down around 130 degrees at 4800 RPM and 110 mph,
MP was
not  noted.

I accidentally hit the cold start switch while on downwind with  two other
planes
ahead of me, and  the tower told me to go around on  final with the engine
stumbling badly, but the plane ahead turned off onto  the taxiway just in
time so
I told the tower that I would really like to  land, so they cleared me.I
still
had 7000 feet of runway ahead of  me.  The engine died as I turned off onto
the
taxiway and then I  noticed the cold start switch. The first order of
business
was making and  installing a switch guard for the cold start switch. I'm
also
going to  pre-load the switch with a rubber band so it stays in the off
position
unless I'm pushing it on, and can just pull the rubber band off of it if I
need
to shut down a set of injectors and run the remaining injectors on  cold
start.(limp home mode for failed injector.)

The fuel self  transferring issue was resolved by installing manual valve
on the
transfer  line between the tanks.



Brian Trubee

Dave Leonard had an  off airport landing because of that cold start switch.
One can get a flip  up guard that covers the switch to prevent  inadvertent
operation.

"The fuel self transferring issue was  resolved by installing manual valve
on the
transfer line between the  tanks."

Are you sure about that Brian?
Did you notice the fuel  pressure when the engine starting running rough?
Could be you sealed the  right tank when you closed the transfer valve.
I suspect the right tank  vent is not working.

Paul Lamar



The right tank vent is  working- I put a piece of tubing over the tank
vent,
opened up the tank  fill, put my ear to it and blew into the tubing- heard
the
air going into  the tank.

But yes- I didn't check the fuel pressure at the staging  point, that's a
good
point, and it's on my to-do list.

Also- to  everyone out there running the EM2- what do you have for
calibration
settings for your manifold pressure- what values do you have for scale
factor,
low end offset, etc? I screwed around with mine and need to get it  back to
where
it should be. Between all those variables, I'm having a hard  time figuring
out
what all these values are supposed to be.


Any  help here would be appreciated.

Brian Trubee



I been thinking about the inadvertent  switching of the cold start  switch
and its consequences as well as how vulnerable that switch is to  accidental
deployment.

I have a simple solution:

Replace the switch with the type of switch that necessitates you to  pull
the lever out slightly before moving it.

This type of switch is used widely in gear operating switches in aircraft
and is available in the miniature size that is used in the EC*. that might
be a  good modification for Tracy to do.

I will do that on my ec-3.

Rich