The Cessna 210 is known to reach high CHT and Oil Temperature.
This problem is dued to the big IO-520 engine being packed inside a small cowl.
The situation is even worse when the engine is turbocharged (TSIO-520) because the turbo uses some space that would otherwise be filled with fresh air. But more important, the turbo is hot!
The pilots use some tricks to keep the engine cool. Let’s see the most important.
- Know how to use the cowl flaps: if the outside air temperature (OAT) is high, just leave them open. Also if you cruise at high altitude the thinner air may not be enough to cool down the engine so keeping them open will help.
- Climb at high IAS: while climbing, the faster you go, the more air enters the cowl. When at more than 1000AGL, climb at 110/120 knots IAS instead of 97 (Vy).
- Cruise at low power: if you cruise at 65% of power, the engine is not going to overheat too much while you get enough speed to cool it down. It must be the correct compromise.
- In hot weather, avoid leaning the mixture unless it’s strictly necessary: the more fuel enters the cylinders, the more cooling is provided.
These are really simple trick that may save the date with a Centurion.
Finally, a note about the CHT and Oil Temperature indicators. Those are old steam gauges and may not be accurate like the modern ones.
Don’t let the needles go near the red line. Maybe the real temperature is already over the red line while the needle is in the green arc.
Keep a buffer between the needle and the red line.
Also, REP simulates the engine detonation (that is, when the fuel in the engine burns by itself without need of the spark plugs, damaging the cylinder heads) that can be triggered by high engine temperatures.