We spent nearly a year looking into and fixing our cooling problems. We
installed temperature probes throughout the engine compartment and
performed data logging on those temps, as well as engine parameters
(rpm, MP, oil pressure, oil and water temps, CHTs, and fuel flow). Each
parameter was sampled once every 2 seconds during flight and downloaded
to a lap-top after the flight. We found that the gills allowed the
upper cowl inlet air to escape without contributing much to engine
cooling. After closing them off, we found no significant rise in upper
cowl temps, but with a noticeable improvement in lower cowl temps.
Closing off the area between the foot wells was the final fix that made
the temps come down, from a max of 450 deg F inside the cowl to a max of
250 deg F.
Regards,
Terry Seaver
A135 / N135TD
XS monowheel with 912S
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Mike Parkin
Sent: Wednesday, April 01, 2009 9:31 AM
Subject: RE: Europa-List: 914 Waste gate servo mounting position
question
I do not have the "gills" open (left them closed since it has been
established that they were a development item providing little cooling
benefit on shut down(positioned too low) and are now a "leftover" item.)
Regards
Bob Harrison.G-PTAG
Bob,
That statement is just not correct. In flight, there is a noticeable
flow of hot air from the gills - obviously aiding the flow of cooling
air across the cylinders. Perhaps that is why you have had cooling
issues on Jabiru and Rotax.
Regards,
Mike
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