That Cold Engine. What to Do?
By Ian Brown, Editor
May 2019 - I wouldn't have understood this if I hadn't read Mike Busch's excellent article, but cold, thick oil is not the main cause of rapid engine wear in a cold engine. It's the reduction of tolerances between dissimilar metals. You can't reduce the risk of exaggerated engine wear by turning the prop a few times to help distribute oil. Mike's suggestion is to put your aircraft in a heated hangar overnight. Failing that, you should invest in an electric engine heater such as Tanis TSP6 or the Reiff HotBand.
Should you permanently heat your engine while in the hangar? Mike's response to that is "No!" If you think about it, permanently heating your engine in a cold hangar gives rise to condensation forming inside the engine on cool surfaces, increasing the chances of corrosion. You should only leave a heater connected for about six hours before you plan to fly, according to Shell and Continental, although it would seem to be okay to me if you plugged it in the night before an early flight, or used a timer to switch it on at an appropriate time through the night.
As an aside, I was interested to read that a new engine with tighter tolerances is more likely to suffer accelerated wear in cold conditions, and now we know why.
