I am experiencing higher than normal oil temps.  It’s not unusual to see 210˚F in the climb.  And then the oil temps remain above 200˚ during cruise.

In the last annual, there was nothing done to the fuel system. The magnetos were spot on.  We also checked the temp sensor to ensure its accuracy against three different thermometers and ran it up and down using a deep fryer with water.  We also pulled the Vernatherm out of the bottom of the oil cooler to ensure it was working.  I also called Rosta mfg to discuss the vernatherm operation.  It cracked open at 150˚ and was full extended by 185˚ per the manufacturer.

In flight, I started playing with the fuel flow to see if I could lower the temps.  What I noticed was that If I put the fuel flow about 250˚ Rich of Peak I could move the oil temp down below 180˚.  I could then hold it using about 225˚ ROP.  I also cooled the motor by reducing the RPM to 2300. 

Anytime I ran the motor below 200˚ROP the oil temp would climb again. This is counterintuitive according to the Oklahoma guys recommendations on running the EGT temps.

As another point of data, I ran the engine LOP and noticed that I could stabilize the temp at 184˚ by running about 45-50˚ LOP. 

After talking to the TCM support staff it would appear that I might need a fuel system setup but I don’t know of anyone that has a fuel pressure system, which will necessitate me taking the plane to a repair station.  That system that TCM recommends is about $5,500. 

Here are some numbers from yesterday’s flight:

 

Does anyone have any recommendations?