I am a little confused as to what may be
going on with my EC-2.
I recently had an incident where the
engine went very lean just after take off and during the climb out to pattern
altitude. I didn’t do any troubleshooting. I just set the
mixture control to as rich as possible and continued in the pattern to land.
On the ground, I could find no problems
with fuel, either tank, fuel pressure, etc.
I decided to follow Steve’s
procedure below. After doing this procedure, the engine ran smoothly from
idle to 22 inches on the ground. I put it into mode 9 and let it change a
few spots on the MAP. Almost all the MAP table was still set at zero.
I taxied out to fly and during the takeoff
run, at about 29 inches and 7100 rpm, the engine went very rich, 10:1.
I adjusted the mixture knob during the takeoff run to about 9-9:30
o’clock. At about 200 feet of altitude, the mixture suddenly went
to about 17:1. I moved the mixture knob to about 3 o’clock, but it
really didn’t help much. When I got to pattern altitude and pulled
the power back, the mixture seemed to stabilize at around 13 or so. I
made the landing and back to the hangar with no incident.
On the ground again I checked the MAP and
the table was at zero at all the places the engine had been operating during
the climb out.
Any ideas?
Bill
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]
Sent: Thursday, January 07, 2016
1:10 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Tuning
Steve,
The following
assumes that there are no problems with CAS or ignition:
After setting
the controller back to all default program values and depending on the update
version of your controller, the following excerpt from archive message #54156
of Mar 6, 2011 may be of interest:
"
The tuning
procedure then becomes the same whether the primary and secondary injector flow
rates are different or identical:
a. Set the staging threshold at a MAP corresponding to the high end of
the primary injector flow limit using mode 7. (For 40 lb injectors, about
20" MAP works well.)
b. Adjust Mode 3 to get a mid scale O2 sensor reading at a MAP just below
the staging threshold MAP.
c. Adjust mode 6 to get a mid scale O2 sensor reading at a MAP just above
the staging threshold MAP.
d. Adjust mode 2 for best operation at minimum idle MAP.
e. Adjust the mixture table throughout the useable MAP range using mode 1
or 9 to keep the O2 sensor reading mid scale. (To be honest, I skip step
"e" and simply use the manual mixture control to adjust the mixture
in cruise.)
"
Steve Boese
RV6A 1986 13B NA RD1A EC2