Sight gauge woe's.
In my experience, the reason for the empty reading in flight is that the
sight gauge is typically hooked to the feed line. Picture those large
coffee pots with the sight gauge on the tap. As soon as you open the
tap, the sight gauge drops. You are getting the same effect. The fix
is to install the Mod 33 and use the drain line as your lower sight
gauge hookup point. The static fuel at the rear of the tank allows the
site gauge to be quite stable in flight. For those of you who put the
sight gauge in the seat back like I have, it works fine (tri-gear). The
longer tube lengths for those of you with the sight gauge near the foot
well, acceleration does cause the fuel to move. Remember to use the
FSO2 to help stabilize the readings.
As for venting of the sight gauge, I put my fuel vents on the bottom of
the aircraft. From the fuel vent fitting (I use a F09C and hook the
sight gauge vent line to the molded fitting, although I have clients
with the standard fitting and the other end of the sight gauge tee'd to
the main vent line), I loop the fuel vent line up to the fill neck, put
a T in the neck (so the gas doen't burp during fueling) and continue up
over the plastic fuel neck, down the back side to a vent tube on the
bottom of the aircraft. I am supplying this info only because it is
different than the stock fuel vent system, and although the low pressure
area on the top of the fuselage is a possible fuel suction point, and or
a ram air point, it shouldn't cause sight gauge accuracy problems, but
it does. The only reason for putting the vent on the bottom initially,
was cosmetics and the nasty fuel streaks down the fuselage when making
low power right turns and getting fuel venting out of the tank in some
aircraft (especially the gliders). Hooking the vent side of the sight
gauge to the vent fitting at the top of the tank was to eliminate the
possibility of suction/pressure influences from the vent to the small
area of the sight tube. The idea was to ensure the top of the tank air
pressure and the bottom of the tank fitting were as stable as far as
flow of air and fuel as possible. It seems to work just fine.
As for the tank leak woes, I have a used fuel tank in the shop which
hasn't had fuel in it for 4 years maybe 5 and am going to fill it to
check for cracks / leaks. I'll post the results if I don't blow up.
Bud Yerly
----- Original Message -----
From: steve v <mailto:s.vestuti@virgin.net>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Saturday, September 08, 2007 5:55 PM
Subject: Re: Europa-List: The Factory Fuel Sight Gauge
<s.vestuti@virgin.net<mailto:s.vestuti@virgin.net>>
Just Thought i would add my "short" experience with the standard
sight gauge here,
i have a tri gear with a compleatly standard text book
intallation with the tube visable in the port footwell, on the
ground the gauge reads fine, airbourne it reads empty - it has done
this
from day one. i intend shortly to dissconnect it and fit a stop end to
the tank as my fuel flow meter is accurate to within half a litre.
could the empty reading in flight be due to acceleration as the tube
runs forward B4 running verticaly?
Steve vestuti G-CEBV #573.
Visit - www.EuropaOwners.org<http://www.europaowners.org/>
http://www.matronics.com/Navigator?Europa-List<http://www.matronics.com/N
avigator?Europa-List>
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