Al,
I had the fuel calibration pretty close at one time, then I sent the unit back for an upgrade and had to start over with calibration. I can see that we generally use the same procedure for calibration. I did use care to calibrate my capaicitive probes very accurately, so I give them more credence at this stage of the game than the EM-2 readings. The EFIS gives me totals in each tank, and the EM-2 gives me total fule on board.
Here's the process I have been using: Power up the EFIS and let it stabilize, total the readings from both tanks, then change the value in the EM-2 to agree. That gives me a starting point. I then compare readings after the flight, and again after adding fuel. After doing this a few times, I can see which way the EM-2 is off and I can tweak the calibration and then repeat the process. After a while, it is pretty close. But like I said, I had it close until I sent it in for an upgrade. I really need to write stuff down. ;-)
Mark
On Tue, Sep 9, 2008 at 10:59 AM, Al Gietzen
<ALVentures@cox.net> wrote:
Currently the fuel burn is registering high, resulting in a fuel remaining reading lower than what I actually have in the tanks. I hadn't made the connection between that and the GPH reading, but now I see that they are inter-related. I usually don't fill the tanks to the brim as I can carry 96 gallons total but I only fly about 100-150 miles round trip. Why carry all that extra weight.
Mark;
I rarely fill my tanks either. I have a calibrated dip stick I use to measure the fuel at one point; then keep track of how much I add over a series of flights; then measure again. Then compare actual measured with EM2 readout, and adjust the FFCAL as discussed in the manual. I have found that difference between EM2 totalizer and measured is different for a 4-5 hr flight than for a series of shorter flights, which I guess isn't too surprising, but it gets you close until you make those long flights.
96 gallons – wow, that should give you quite a range.
Al