OIL COOLERS
Does the oil cooler have a thermostat internally ? If so which end ? My oil cooler is mounted vertically at the rear top left side of the engine on the back baffle.
So if I drain the oil from the sump, does it drain out of the oil cooler as well ?
The reason I ask is that over the ten years I have had my aircraft, I have noticed that the oil temp has gone up. Not with the outside summer heat but in general also in the winter. The yellow arch starts at 180 and it is often above that but well below the red line. The aircraft is very tightly cowled, so in the winter it is a juggling act to keep the CHT cool on the ground before the oil warms up, in the climb the CHT is quite high, but once in cruise the CHT is OK. The oil I use is Shell multigrade 15/50.