Oil temps in the climb, again

[207WF]

Before the summer heat makes this an issue again, I have another hypothesis about oil temps in the climb and would like some help to see if it makes sense. My hunch is that the problem is related to how the radiator sits relative to the opening in the cowl. Some planes have the high oil temp problem, but others do not. Please chime in with your data:

 

I have high oil temps in the climb. For example at 25C it stabilizes about 240 F in a cruise climb (full throttle, 95 knots). At 30C it can approach the red line.

 

There is a gap between the top of my radiator and the cowl opening that is just over 3/4 " wide.

 

I would like to know how large are these gaps and what is your oil temperature experience in the climb.

 

thanks

WF

[Ed Cesnalis]

wayne,

 

have you yet confirmed that your high readings are in fact correct readings? i have not and i remain skeptical that i am getting as hot as the gauge is indicating.

 

altering flap settings changes my pitch attitude a lot. i assume cowling air flows change with the different pitch attitudes yet i will be hot in any of them.

 

i even cruise a little hot if ambient is about 69degreesF.

[207WF]

Ed, I would like you to measure the gap between the top of your radiator and the cowl inlet and let us know what it is. WF

[sandpiper]

My gap is about 3/4" and, yes, I have oil temp problems in the summer. I also have a long climb to get over the mountains as my airport is 175 msl. Some days, getting to 9000 msl can be a chore. I either step climb or hold a higher airspeed and/or back off the throttle a little. I wonder if sealing that gap would force more airflow accross the radiator and, would doing that create another problem.

 

Somewhere I saw posts with pictures of lower cowel modification that apparently worked. If FD would approve that modification, and the cockpit controlled radiator shutters, that would probably solve the problem. This summer I will also go the next richer notch with the carb. Roger says it helps.

 

It is frustrating to have a plane with the CT's performance then not be able to use it. To be clear, I'm not just talking about yellow band on the indicator. Mine will easily go to redline if I don't stay on top of it.

[207WF]

Let's here from someone without the oil temps in the climb problem. What gaps do you measure? WF

[westcoastoz]

Let's here from someone without the oil temps in the climb problem. What gaps do you measure? WF

 

 

The gap on my 2006 CTsw is around 3/4" and I have never had any problems with excessive oil temperatures, in fact quite the reverse.

Some years ago, I retrofitted a PermaCool oil thermostat to try and alleviate low oil temps. so as to avoid having to tape the radiator, but as reported in a thread on this subject on another forum, it made little difference.

I flew the airplane yesterday with ambient temperatures at sea level of 37C (98F) and the highest I saw the oil temp. in the climb (at 90 KTAS)to 7500' was 110C (230F).

In winter (very mild in this part of the world) I would never achieve 100C (212F)in the climb without taping the radiator.

 

WF, if you have the Dynon EMS, have you compared the temperatures of the CHT, EGT & Oil after the airplane has been not been flown for a while (overnight at least) to ensure that the ambient oil temp. is comparable with the other indicated ambient temps?

 

Regards,

 

Dave