High Oil Temps

[dallen]

I have a standard Onex w/2180 Aerovee with the top mounted oil cooler. No external oil filter. On the first three flights I'm experiencing oil temps from 235 to 240 just over the max. The engine has only 3.5 hrs on it.

Just wondering if other Onex owners are experiencing the same and what they done to bring the temps within the safe range. Or should the temps settle down as I get more hrs on the engine.

I was expecting high CHT's which I seem to be able to control w/throttle settings but once the oil gets over the 230 even at idle it won't come down within range.

Dave
ONX-019

[MichaelFarley56]

Quick question for you Dave: how is your oil cooler shrouded? Do you have the "telescope" off the back of the oil cooler running to the aft baffle piece? Just like the cylinders, your oil cooler needs proper ducting so that air has to go through it rather than just around it. My AeroVee has the Onex style upper oil cooler setup and even with warm temperatures during the Oshkosh trip this week, my oil never got above around 190. I made sure there's an oil cooler duct from the back of my cooler to the rear baffling so air could go through the cooler.

Also, how much oil do you have in your engine? Running with improper amounts of oil can have negative effects as well.

You are correct though...the oil temperatures will drop as the engine breaks in to a degree, but hopefully we can figure out why it's so hot right now!

[fastj22]

The Jabiru 3300 is very sensitive to how much oil you have. If you even have a few ounces too much oil, temps spike.

[dallen]

Thanks Mike for your reply, I have 2 3/4 qts. of oil installed and I did shroud in the back side of the cooler to the aft baffle piece. I had my baffles already installed when Sonex came out with the revised dwgs so it's not exactly the same as the revision.

Somehow, I need to direct more air through the cooler. Also, I have one of those aftermarket sumps that adds 2 qts. of oil to the motor for a total of 4 3/4 qts. So I'm going to try installing that and see if I can direct more air through the cooler. Hopefully that works.