Oil Still Too Cool Even With Cover

Hi Sean,

"Personal view; I do not like the added complexity & weight of an oil thermostat. Ugh! to all those added connections/failure points."

I'm with you.

For my last 12 years I have fitted the oil cooler half in, half out of the cowling and underneath directly behind the exhaust muffler.  The cooler is attached to the engine frame. I made a simple hinged flap in the cowling operated by a friction cable (adjustable) so the airflow over the cooler can be from full hot air coming from over the muffler or at the other end of the cable, fully cold outside air.  This works perfectly, oil temperature fully controllable to get +100 during flight for the required time, all other times adjusted to about 90C. ?

John Harris wrote:

For my last 12 years I have fitted the oil cooler half in, half out of the cowling and underneath directly behind the exhaust muffler.  The cooler is attached to the engine frame. I made a simple hinged flap in the cowling operated by a friction cable (adjustable) so the airflow over the cooler can be from full hot air coming from over the muffler or at the other end of the cable, fully cold outside air.  This works perfectly, oil temperature fully controllable to get +100 during flight for the required time, all other times adjusted to about 90C. ?

I would really appreciate some photos of your cowling/oil/coolant installation

I used to blank off part of the oil cooler in winter but I still spent too much time trying to warm up the oil before taking off and was just marginal in cruise. Installed an oil thermostat 6 years ago and find it works great, oil is warm enough after taxi for departure and don’t have to dink around with a blank off anymore.