912 and "waterless coolant"
in 912 / 914 Technical Questions
10 years ago
Greetings! My first post on this forum. :)
I received notification from my aircraft manufacturer of Rotax TR-IM 912-001R1. Page 6 states that IMPORTANT:
Waterless coolant formulations (Evans, or others) are NO LONGER APPROVED for use in any 912 or 914 engines equipped with the "New Style" (2013 or later) cylinder heads.
(see the TR documents for complete details...)
See: http://legacy.rotaxowner.com/manuals/tr-im-912-001-r1.pdf page 6.
I was wondering if anyone had an idea of the technical reason for this reversal.
Even though Evans Waterless coolant was the recommended coolant, it was left to the manufacturer to put in whatever they prefer...P&M Aviation puts 50/50 conventional in their aircraft.
Last summer I was having an issue with my engine boiling the coolant in the #4 cylinder head after shutdown and forcing a fairly large amount (1-2 oz.) of coolant into the recovery bottle. Upon cooling to ambient, the system couldn't draw this much coolant back into the system leaving the expansion tank low.
After changing to Evans, I've not had this issue. The engine runs 10 degrees warmer with Evans but is still well within tolerance (200 degrees F even on the warmest days).
Gotta say, I'm not excited about this...
Thanks in advance.
Chris
I received notification from my aircraft manufacturer of Rotax TR-IM 912-001R1. Page 6 states that IMPORTANT:
Waterless coolant formulations (Evans, or others) are NO LONGER APPROVED for use in any 912 or 914 engines equipped with the "New Style" (2013 or later) cylinder heads.
(see the TR documents for complete details...)
See: http://legacy.rotaxowner.com/manuals/tr-im-912-001-r1.pdf page 6.
I was wondering if anyone had an idea of the technical reason for this reversal.
Even though Evans Waterless coolant was the recommended coolant, it was left to the manufacturer to put in whatever they prefer...P&M Aviation puts 50/50 conventional in their aircraft.
Last summer I was having an issue with my engine boiling the coolant in the #4 cylinder head after shutdown and forcing a fairly large amount (1-2 oz.) of coolant into the recovery bottle. Upon cooling to ambient, the system couldn't draw this much coolant back into the system leaving the expansion tank low.
After changing to Evans, I've not had this issue. The engine runs 10 degrees warmer with Evans but is still well within tolerance (200 degrees F even on the warmest days).
Gotta say, I'm not excited about this...
Thanks in advance.
Chris
