912 oil system

Depends on your latitude, i suspect.  I’ve worried about all that cold oil being way over in the tank in cold weather.  I don’t have a heater, but I’m thinking about it.  Another oil cooler in that circuit before the engine gets warm sounds problematic for those of us with cold weather. 

I added an oil thermostat. It restricts the oil flow to the engine until it reaches 190f. That takes care of my cold weather flying. I also added a second oil cooler to handle the hot weather flying. Now my warm ups are quick and oil temps are never too high regardless of the OAT. 

https://waltsrv12.com/engine/adding-second-oil-cooler/

Hi Walt,

I admire your ingenuity and the quality of your workmanship but wonder at the degree of complexity.

I am not sure if the Rotax requirement for an oil cooler is still current ie none, however this is the starting point for oil cooling design.

I do not know of a Rotax 912 ULS installation that does not use an oil cooler.

Rotax offer, I think three oil cooler sizes, as in Standard, Large & Extra large - one of these may have met your requirements.

I have a tight installation, not too dissimilar to yours and have, after many modifications to cowling air flow had little effect,  upgraded from the Large to the Extra large cooler.

My cooler is located in the cowling exit air - no additional ducts. 😈

Sean, unfortunately the cowling on the RV-12 does not allow for a larger oil cooler. There are many other airplane designs, apparently yours, that a larger cooler will fit. I live in a climate where high temperatures are common and I don’t care much to step climb to allow the engine to cool in between. This is what worked for me, it proved that the engine temps can be managed without sacrificing aircraft performance. 

".......unfortunately the cowling on the RV-12 does not allow for a larger oil cooler. "

I take your word for it.

My Sonex Legacy with custom cowling is very tight. The oil cooler is located, bottom of firewall, in the exit air stream. I got the idea from my last aircraft, an ATEC Zephyr/912ULS. Seems to work well despite this being warm air.

I live / fly in Australia - not uncommon to see summer temps 40C, occasionally 47C , with winters as low as 0C (usually in the low teens). When day temperatures are consistently below 25C I block off part of my oil/coolant radiators.😈