As cold weather approaches, I want to remind all of you that it’s critical our engines are kept pre-heated. When you arrive to fly, you should find the aircraft pre-heater plugged in and operational and the engine should feel warm to touch. Our 172 has an engine block pre-heater that simply plugs in using an extension cord. The 182 has a hot air system for which you’ll need instruction on placement of the duct. We will be moving the 172 into a hangar shortly, but there is power on the pole at the tie down that should be used.
Engine preheat is important for a couple reasons, and not for the reason you might think. We use a multi-viscosity oil which flows well when cold, so sludgy oil isn’t the issue. The real issue is internal engine clearances. Because engines are made of dissimilar metals that expand and contract at different rates, a cold engine may not have enough clearance in its bearings for oil to lubricate adequately. Starting a cold-soaked engine can cause serious engine damage in just seconds and reduce time to TBO. In other words, cold starts can be extremely expensive. Secondly, even when all engine gauges are in the green, a cold-soaked engine may still have components cold enough to impede lubrication which has, in a number of cases, even after long ground runs, caused engine failure after take off. So, in a word: preheat! It’s safer and saves you money.
For more information: a detailed article from AVWeb.
When returning from a flight, you should plug the pre-heater back in so that the engine stays warm for the next flight. Engine pre-heaters are self-regulating and are intended to be kept on at all times through the winter.