Hi all,

Perry, I would like to know what typ of cooler both mentioned oilcoolers
are:
I am a little lost with cooler-lingo, but how do they work: A tank on each
side with a couple of crosstubes or are they one/two/three tubes that wind
back and forth?

The reason why I asked is, if both are the typ with 2 tanks and crosstubes
(huge cross section, slow flow thru the cooler), it depends where the
inlet/outlet is placed and if the cooler stays full with oil when stopped.

A couple of years back (about 15 or so) I thought of putting an oil-cooler
on my BMW R100S, but got warned by some people, that if you would not bleed
it right, it would not work - it seems that both inlet and outlet where
pointing down as this was the shortest connection to the pump, the cooler
was up in front of the engine on the frame. The oil would feed into the
inlet tank and start to compress the trapped air in the cooler, so only the
one or two lowest crosstubes would feed oil to the outlet tank, waisting the
majority of the cooler on trapped air! The solution was to change the outlet
to the top so any trapped air would be pumped out. As it was it still
worked, if it was bled correctly on installation, as the oilpump would hold
the oil. However over time air would get in and the original cooler
configuration had to be bled on a regular basis.

Any chance something similar could have happened to your 12A cooler?

Thomas J.

Maybe, I don't know. The oil cooler is a two pass, and oil was
definitely going through it, it would be warm after landing. There is a
thermostat bypass, I know that was working because the temp would only
drop to 150F and sit there during descents.
With the 82 cooler in the cowl the ports were at the front and the front
was slightly lower than the aft end, possibly trapped air, but wouldn't
oil pressure force it out?

--
Perry Mick
Custom Composite Props
mick@bridgingworlds.com
http://www.ductedfan.com

 
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