Rowland,
I place the coolant overflow on the starboard side and it is accessible
through the oil door on the XS.
Glycol is my choice in the hot climate of Florida. In cool climates Evans
is fine.
Rotax requires coolant outflow to be monitored as the owner who chooses to
run at 275 will boil glycol in the head. New engines have new heads and
coolant monitoring.
I find the in line coolant temp probe to be more of a pain and inaccuracies
than it is worth. Don't let the cylinder head temp go above 245F and the
coolant never boils over.
Because Evans has nearly 20% less heat transfer ability, it is essential to
optimize your cooling or enlarge the radiator in hotter climates. Good news
is, Evans is lifetime and frankly, it does not appear to corrode as
water/glycol can.
In the UK you should be fine with a 912S, even on long taxis and hard climbs
at 90 KIAS provided you paid attention to your ducting.
Best Regards,
Bud Yerly
-----Original Message-----
From: Rowland Carson
Sent: Sunday, May 15, 2016 2:14 PM
Subject: Europa-List: coolant choce and temperature monitoring questions
I thought Id got all the instrumentation I needed sorted out, but Ive come
across the following items in the Rotax Installation Manual:
"2 different types of coolant are permitted.
Type 1:
- Conventional coolant based on ethylene glycol
Conventional coolant is recommended as it is commonly available and has a
greater thermal heat transfer capability.
. . .
Permanent monitoring of coolant temperature and cylinder head temperature is
necessary.
Type 2:
- Waterless coolant based on propylene glycol
Waterless coolant is recommended if the design of the aircraft can not
maintain the coolant temperature limit.
. . .
Permanent monitoring of cylinder head temperature is necessary.
Additional monitoring of the actual coolant temperature is possible but not
necessary for waterless coolant.
I seem to recall that Evans (waterless) coolant was the flavour of the month
some time back, and then it fell out of favour. I understand it's more
expensive than ethylene glycol coolants as well as causing the engine to run
hotter (because it doesnt transfer heat so well).
However, it appears from the above Rotax manual extracts that if one wants
to use the cheaper ethylene glycol option, its necessary to have a coolant
temperature gauge as well as the CHT monitoring. And elsewhere in the manual
coolant temp monitoring is required during the test flying period even with
waterless coolant.
So, the question is - what do folks in UK generally use in the coolant
system? And if conventional ethylene glycol, what type of coolant
temperature sensor do they have and where is it fitted?
All advice born of experience welcome.
in friendship
Rowland
| Rowland Carson ... that's Rowland with a 'w' ...
| <rowlandcarson@gmail.com> http://www.rowlandcarson.org.uk
| Skype, Twitter: rowland_carson Facebook: Rowland Carson
| pictures: http://picasaweb.google.com/rowlandcarson
|