The other variable (which is consistent with your original theory) is change of
season. The temperature differential between warm humid days and cold nights
is relatively high at the moment.
I never saw water in the plastic tank either, but have a 'plastic' filler pipe.
Duncan McF.
----Original Message----
From: brian.davies44@gmail.com
Date: 10/10/2018 09:11
Subj: RE: Europa-List: Occasional engine anomally 912S - water?
Hi Graeme,
A couple of things come to mind.
First, whenever you disturb the fuel system there is a high possibility of
debris moving and temporarily blocking a jet.
Secondly, there is always a danger when you mix fuel containing ethanol with
non-ethanol fuel. Fuel containing 5% ethanol will absorb water until it
reaches its limit and will then undergo phase separation, creating a layer
of pure water. If your 5% ethanol fuel has already absorbed a fair amount
of water and you then fill up with non- ethanol fuel you lower the overall
ethanol percentage of the fuel in your tank and hence its ability to contain
the absorbed water. Phase separation can then take place, probably in
relatively small quantities of water, so this may explain why you are now
getting water out of the drains. The solution is to drain all of the fuel
out of the tank and fill up with Esso Supreme.
This is all theory of course, but worth doing I would suggest.
Regards
Brian Davies
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of graeme bird
Sent: 10 October 2018 08:33
Subject: Europa-List: Occasional engine anomally 912S - water?
On several occasions now, after some time flying (40+ minutes) the engine
has had a minor episode, like one mag has been turned off for half a second.
It then continues as normal (with me looking for a field). It seems
unrelated to temperature or phase of flight, icing conditions, or
turbulence, except perhaps initiating a slow descent.
I have had a good think around the possible causes and why just these last
few months; one thing I did was change to using Essso Supreme (no ethanol)
---From ordinary Shell unleased; the other was to change the long filler tube
to aluminium (classic style).
Recently using the tank drain plugs I have noticed a small amount of water
in the fuel (I'm not in the habit of checking this regularly as there was
never an issue).
So my current theory is, air is filling the long aluminium tube via the
breather and is trapped, when the temperature drops in the hangar
condensation forms on the inside of the tube and enters the fuel, either
that or the Esso S+ garage supplies it with water in.
It would fall into the starboard side of the tank but after 40 minutes or so
the fuel return to the bottom of the starboard side and roll/pitch changes
may have mixed the water and fuel sufficient that it is sucked into the port
fuel line, into the carb bowl and eventually into the engine at which point
the mixture refuses to burn for a beat or two. Once good fuel is back it
carries on. The old tube was rubber so this wouldn't have happened.
--------
Graeme Bird
G-UMPY - Mono Classic/XS FFW 912S, Woodcomp SR3000/3W CS, trutrak Gemini 2
axis AP, PAW, PFLARM core, ads-b out, 8.33khz, mode S, FP-5, Aera500, SD on
Nexus, Smart A3
350 hours & 6 years on the Mono, 930 total
g@gdbmk.co.uk
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=483747#483747
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