On my Classic Europa with 912UL, I am experiencing too high oil temps for
comfort.
Full power climb will run the oil temp to the very edge of the red zone after
less than a 1000' climb, settling to well above 120 degrees C in 65% power
cruise. I rarely see oil temps below 120, except in winter.
A while ago Frans made quite a convincing argument that the tandem setup of the
water and oil cooler is far from optimal, ideally I should give the oil cooler
a dedicated inlet.
Before going into such a substantial modification, I decided to close the gaps
between engine cowl and water-cooler, as well as the gap between oil and water
cooler to see what that brings in term of oil-cooling. Attached picture give
you an idea of the significant gaps between cowl and water cooler.
I completed the first part of this little project: putting in a vertical plate
around the water cooler. This plate blocks air from entering the cowling
undisturbed,
and will serve as a plate that rubber seals will be sitting against.
I was stunned to see the enormous effect this vertical plate alone has on oil
temp:
a drop of about 8 degrees C compared to previous flight with almost identical
OAT. This time even after a 2000' full power climb, the oil temp would not
exceed 130 degrees C. I am now hopeful that closing the gaps on the sides will
bring the oil temps down to an acceptable level.
A long intro from my end, leading up to a couple of questions:
* What type of rubber sealing should I use, is it Silicone because of its
resistance
to high/low temps? And: who sells small quantities of whatever type is required?
* What relation, if any, is there between width of gap to seal and thickness of
the seal?
Reasons for this question: on the propellor-side of the inlet I have a gap about
13 mm between cowl and radiator, does this ask for additional measures to
prevent
the seal from being pushed to the propellor-side of the radiator by the
high-pressure bubble in front of the cooler? (this would open up the gap again,
allowing air to escape)
* I intend to attach the seal to the inside of both halves of the cowl. Two
reasons
for that: (1) on the inside the seals won't disturb the airflow to the radiator,
and (2) aesthetics.
What is the best way to attach them to the glass cowl (ideally without
disturbing
airflow by rivnuts or what else sticking out in the flow of incoming air to
the rad)
* A gap exists between water and oil cooler; top and bottom gap is about 1.5-2
mm, gaps on both sides are about 5 mms. These need to be closed up as well, but
until now I have not come up with a good idea for this.
How did you seal this? All suggestions are more than welcome! (with some pics if
not too much trouble please)
* Finally, I need to close a 0.2-0.7mm gap between cooler and installed vertical
plate. How can I best attach silicone rubber to metal, wide-head rivnuts with
supporting strips or will an oversized (say 2mm) sponge-type silicone profile
with adhesive-back suffice?
--------
Marcel
(Europa Classic Tri-Gear PH-MZW)
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=353334#353334
Attachments:
http://forums.matronics.com//files/ph_mzw_water_cooler_gap_625.jpg
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