Hans,
Tried to find the documentation from Rotax requiring the installation and use of
the "Fuel/AirBox Differential Pressure Gauge" but can't find it right now.
In any case, Rotax now requires that a gauge and sensor system be installed to
monitor the differential between fuel pressure and airbox pressure to ensure
there
is always sufficient fuel pressure to overcome airbox pressure in the carbs
preventing fuel starvation issues. It also allows detection of excess fuel
pressure which can cause the problems you already described.
UMA makes the system. I know that it is available from Aircraft Spruce:
http://www.aircraftspruce.com/catalog/inpages/umafuelairbox.php
And is probably available from other vendors as well.
Good luck in solving your fuel pressure problems. As you previously stated,
there
is probably some restriction in your fuel return.
Check six,
Bob Borger
Europa Kit #A221 N914XL, XS Tri-Gear, Intercooled 914, Airmaster C/S Prop
http://www.europaowners.org/forums/gallery2.php?g2_itemId=60232
http://www.biplaneforumgallery.com/index.php?cat=10046
Europa Flying!
3705 Lynchburg Dr.
Corinth, TX 76208
Home: 940-497-2123
Cel: 817-992-1117
On Oct 17, 2010, at 12:10, Hans J. Danielsen wrote:
> During my studying in order to rectify my too high fuel pressure indication
> (which
for my 914 installation most probably is caused by a restriction - one way
or another - in the fuel return line), I'm astonished to (re)learn that there
is no requirement from Rotax to install a fuel pressure instrument.
>
> The Installations Manual states: "There is no standard connection provided to
measure the fuel pressure. For general observation and at engine troubles fuel
pressure readings would be helpful". The text further describes how to go about
fitting of an extra banjo bolt etc.
>
> In other words: It's entirely up to the builder - or to follow local country
requirements - to install such an indicator.
>
> Nevertheless: The Rotax Operations Manual issue a warning (page 2-4) which
> says:
"Exceeding the max admissible fuel pressure will override the float valve
of the carburetor and to engine failure".
>
> I would say that a check of the pressure would be damned "helpful" in this
> respect!
Or, how would I know at all of any ill funktion before the donkey elects
to stop over the biggest lake in Norway???
>
> Now, can someone explain to me why the Rotax factory has such an indifferent
approach to this issue in the Installations Manual, while the Operations Manual
"paints the devil on the wall" in pointing out the dangers. And, there is no
follow up whatsoever in procedures or check lists for high fuel pressure, as
with other abnormalities. In other words: Rotax issue a Warning based on an
abnormality
you wouldn't stand a chance to know - if you didn't find it "helpful"
to install the indicator system!
>
> This can't be right!
>
> Hans
> LN-HJD, #334
|