AlexPeterson
Well Known Member
This is side branch of another thread regarding cell phone/pager remote heater operations.
Bob M. asked a question regarding possible down sides to 24/7 engine heating, and relayed their group kicked it around and said it could drive moisture into the oil sump.
Water liberated by heat in one area of the engine will drift towards and possibly condense in other colder areas of the engine. (This is an important process, as it is how a whiskey still works!)
So, when hot air is blown into the cowl, the cylinders clearly heat first, liberating moisture from those. The oil sump will take much longer to heat up, so yes, moisture probably does migrate to it. How much moisture is present in the cylinders to do this? Wouldn't seem like much.
The potential issue with heating only the oil sump is the opposite - moisture liberated from the sump condenses in the cylinders, which are constantly being cooled by convection of air moving through the cowl.
From a scientific point of view, heating the whole engine uniformly is what is desired. Any sort of heater in the lower cowl, preferably on a thermostat, is a good idea. The cowl needs to be reasonably sealed and blanketed. I use foam plugs in the inlet/outlet areas, and a blanket around the whole outside of the cowl. The entire cowl is then uniformly heated to 70F, for example, if a thermostat is used.
I put a hobbs like counter on my engine heater one winter to see just how much it ran in a 45F hangar. It ran about 1/3 of the time, costing perhaps $6/month, with the thermostat set at 70 under the cowl.
Bob M. asked a question regarding possible down sides to 24/7 engine heating, and relayed their group kicked it around and said it could drive moisture into the oil sump.
Water liberated by heat in one area of the engine will drift towards and possibly condense in other colder areas of the engine. (This is an important process, as it is how a whiskey still works!)
So, when hot air is blown into the cowl, the cylinders clearly heat first, liberating moisture from those. The oil sump will take much longer to heat up, so yes, moisture probably does migrate to it. How much moisture is present in the cylinders to do this? Wouldn't seem like much.
The potential issue with heating only the oil sump is the opposite - moisture liberated from the sump condenses in the cylinders, which are constantly being cooled by convection of air moving through the cowl.
From a scientific point of view, heating the whole engine uniformly is what is desired. Any sort of heater in the lower cowl, preferably on a thermostat, is a good idea. The cowl needs to be reasonably sealed and blanketed. I use foam plugs in the inlet/outlet areas, and a blanket around the whole outside of the cowl. The entire cowl is then uniformly heated to 70F, for example, if a thermostat is used.
I put a hobbs like counter on my engine heater one winter to see just how much it ran in a 45F hangar. It ran about 1/3 of the time, costing perhaps $6/month, with the thermostat set at 70 under the cowl.
