Hi! Mike
Yes we all find that the cooling problem solving is a black art . The
only positive thing I gained from my Jabiru 3300 was to understand that
on a completely air cooled installation (excepting the oil cooler of
course) the top of cowl has to have pressure maintained to push hot air
down (against physics . hot air rises!) and so away. My Rotax
installation has the third cooling air intake hole linked to the
fiberglass hood forcing air down through the barrels not unlike the damn
Jabiru! The authorities said NOT to cut that hole out on a 914, I am so
pleased that I did.
I'm pretty sure I would concur with Terry about closing off the rear of
the engine down between the foot wells, all goes to achieve overall
cooling at the scource.the guts of engine.by improving the down draught.
Air flirting over the top isn't slow enough to pick up any therms !
Regards
Bob H G-PTAG
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Mike Parkin
Sent: 02 April 2009 07:08
Subject: RE: Europa-List: 914 Waste gate servo mounting position
question
Bob and Terry,
I must say that I find the subject of Europa cooling most baffling
(pardon the pun). G-JULZ is constructed absolutely 'bog standard'
apart from the addition of the Singleton firewall. My 914 engine
pre-dates the later ducting and stuff that is fitted around the
cylinders. You may recall that I had the cooling issues in Switzerland
some years back which prompted me to lower the oil cooler from behind
the radiator. Since then my problem has been getting the engine up to
temperature to take-off - particularly in winter. It is true that the
Evans coolant had an adverse effect such that in a sustained climb
during the summer the engine temperature climbed quickly such that I had
to level off early to control the temperatures. I think that the heat
transfer properties of the Evans being less than that of water/glycol
was enough to push the cooling system beyond its capability on a hot
day. I am just completing the modification paperwork for my cowl flap
which may or may not have any effect - certainly these days - trying to
keep the engine temperatures up particularly in the cruise is the main
problem. CHT and Oil temperatures circa 60-70 degs C are not unusual
once established in the cruise. It is curious that some people have
major cooling issues and other people don't. Perhaps I am missing
something. I have just fitted a water temperature gauge which might
help identify any problems. In light of Terry's experience, I will be
watching the whole thing much more carefully.
Regards,
Mike
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