I've recently found that a 40 amp alternator is not sufficient to run a 13B with electric fuel pumps and EFI. Seems the injectors take up a huge amount of amperage at higher rpms. I'm fine on the ground,- at about 13.7 volts, but when I'm running 5-6000 rpm, my voltage starts dropping and stabilizes at a little below 12 volts after an hour of flying. I have two 18 AH batteries. I"ve got a Dynon D10, terra 250 Transponder, Xcom radio, EC2, EM2, and two fuel pumps from RWS. I only run one pump at a time except for takeoff and landing. Anyone know what the current draw for the injectors is at 6000 rpm?
Looks like I need to add another alternator.
Brian Trubee
-----Original Message-----
From: Steven W. Boese <SBoese@uwyo.edu>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Thu, May 31, 2012 6:45 am
Subject: [FlyRotary] Re: Injector balancing
Mark,
I would really encourage you to try Ed's suggestion of disconnecting any external devices from the fuel injector circuitry. The fuel injectors are like any other solenoid device where the
current required to hold it open is only a small fraction of the current required to open it in the first place. The likelihood
that the connection to the external device is only made to one injector would make this an even more useful thing to try.
RV6A, 1986 13B NA, RD1A, EC2