Roland, I had endless problems with overheating with my 914/XS. Going to
LAA Rally was a nightmare, because sitting in a queue to take off always
led to overheating, needing me to pull out of the queue and shut down. I
then had a Woodcomp SR2000 which is a low twist prop, very much like a
Warp Drive one or pretty much any prop you see on a Rotax 91X. The
problem is that at idling speeds the central part of the prop is in Beta
mode, effectively diverting air from the cooling inlets. When I switched
to a Woodcomp SR3000W the problem was abolished completely, quite apart
---From gaining an appreciable amount of performance (equivalent to an
extra 7 horse power). I can now sit in a queue all day if needs be!
Details in the attached paper which appeared in the Europa mag some
years back. Photos are missing but not needed for understanding the
science. Regards, David Joyce, G-XSDJ On 2016-07-28 11:22, Roland wrote:
> Hello, I have the conventional XS cowling with the 914 and overheating might
occur on the ground in high OAT's (25-30C). I've shut down the engine once when
reaching 118C and then I could hear the 50/50 antifreeze boiling lightly. Does
anyone know roughly the temperature gap between the CHT/CT (I only have a CHT
gauge)? I've read on another forum, that increasing to 2700RPM (and switch
to a courser pitch?) brings down the temperature. I also have a water
Thermostate
installed, which I'll remove in a first step to lower the CHT-temperatures
on the ground and increase the time until I have to shut down the engine (when
reaching 115C CHT). With this measure I (hopefully) increase the oil temperature
at the same time (oil cooler partly covered by Radiator) so that I can taxi
and take off earlier, since I don't have to wait for the oil to warm. Same
goes after landing regarding the cooling run for the Turbo, when the CHT is
creeping
up quickly. What ar
e your
experiences especially without water Thermostate on the ground in high
temperatures / measures to avoid overheating? I want to start with simple
things before modifying the cooling tunnel, because I "only" have issues on the
ground and quite satisfying setup for flying. Also modifications often end in a
never ending story and often the only practical solution might be the best
compromise... The cooling of the XS is only sufficient for English summers I'm
afraid :-) Roland PH-ZTI XS TG 914 Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=458822#458822 [1] [1 [1]]
Links:
------
[1] http://forums.matronics.com/viewtopic.php?p=458822#458822 [1]
[2] http://www.matronics.com/Navigator?Europa-List [2]
[3] http://forums.matronics.com [3]
[4] http://wiki.matronics.com [4]
[5] http://www.matronics.com/contribution [5]
Links:
------
[1] http://forums.matronics.com/viewtopic.php?p=458822#458822
[2] http://www.matronics.com/Navigator?Europa-List
[3] http://forums.matronics.com
[4] http://wiki.matronics.com
[5] http://www.matronics.com/contribution
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