Oil temperature and Constant Speed

I recently changed my 3 blade Catto out for a 3 blade MT. I have never seen my oil temps above 190 for the past 500 hours. I’ve got one hour on the MT in phase one again, and I’m seeing oil temperature up to 208 in the climb up to 5000’. After level off it stabilizes down to 186 where it normally runs. What would cause this? My hunch is I’m producing more power with the higher rpm.

Oh- and wow- that push in the seat on take off is amazing…

Planecrazy232 said:

My hunch is I’m producing more power with the higher rpm.

Click to expand...

Good hunch.

Way back in the NACA days, the wizards wrote that cooling demand was proportional to mass flow. Our engines are air pumps, and setting aside changes in VE across the range, mass flow is proportional to RPM.

Prove it to yourself; pull the blue knob until RPM is the same as it was with the fixed pitch and see what the oil temp does.

Yep, that push in the seat is "generated" by something, and it has a byproduct. . Isn't it nice to have full horsepower available at all (most) times.