Bring down oil temperature on a 912 Vz

Hi Till

I am perplexed - 

Are you talking oil and/or coolant temperatures?

Why would you want to fit a thermostat (oil/coolant?) if you are struggling to keep the temperature low? My understanding of thermostats is that they are installed to maintain a desirable (?) high temperature - they do nothing for keeping a liquid (engine) cooler.

Oil coolers & coolant radiators, are heat exchangers, both do the same thing for the liquids contained within. - essentially they increase the surface area of the liquid, by channeling it through multiple galleries, so that air can carry the heat away. More galleries (larger radiator/cooler), usually results in more cooling effect.

The other part of the system - airflow (in/out) must be provided to have sufficient air moving through the heat exchangers to carry the heat away.😈

What Sean said. Looks like you need an intercooler for cooling the combustion air or improve air flow thru the radiators or both.

Thanks Sean & Sam! To clarify:

I'm generally looking to bring down the engine temperatures and would consider all options. Since both oil coolers and coolant radiators cool the engine I was hoping making them bigger might help. Which one would have a bigger cooling effect if it was upsized? The airflow around them is already well designed and I even built funnels to optimize the air flow through them.

I mentioned the thermostat and the lower end of temperatures because obviously having more cooling capacity will have the adverse effect of potentially cooling the engine down too much on a long descent. I already have this problem after crossing mountain ranges and descending on low RPMs - on cold days the oil temp can go as low as 50°C which is undesirable and should be preventable by installing an oil temp thermostat that cuts out the oil cooler from the circuit.

Hi Till,

Are you able to seal up the air ducting that supplies the heat exchangers. I get a noticeable decrease in cooling temps when I seal mine up with tape, so that might be worth a try. 

Hi Murray,

thanks for this input. I have already built an aluminium funnel to optimize airflow onto the oil cooler. Please see the attached picture of it.
I haven't yet sealed the gaps with tape. It would need to be removed whenever I take off the lower part of the cowling. Do you reseal every time after you take off your cowling?

The coolant radiator is mounted under the engine near the firewall. I haven't taken the effort of designing a funnel. It has a big air duct and appears well ventilated. Do you funnel to your coolant radiator and seal with tape?

The oil cooler is a bit off-center to the left of the plane. That's why I believe a bigger one could be fitted.