Any devices for keeping an engine dry?

peter-h

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peter-h
A lot of airplanes don't fly very often and this is generally regarded as being the #1 cause of internal engine corrosion.

I am hangared and fly every week but for the past few years I have been keeping a couple of 0.5kg bags of silica gel in the cockpit, renewed every time I fly. I bake them overnight at +120C to recover them. A primitive measurement with an electronic RH meter suggests that the cockpit RH drops about 10 percentage points, which is an awful lot if the outside air is 99% RH :) The condensation potential improvement between 99% and 89% is huge.

One can achieve a similar effect with a heater; raising the temp lowers the RH. But that requires constant power which most hangar customers cannot have.

An unpressurised airplane will limit the improvement, due to various orifices. But my cockpit still smells like new, after 7 years.

Anyway, I was wondering if anybody does something that can be attached the the exhaust pipe and which blows dry air up there. A simple device with a bag of silica gel, a tiny fan, could be battery powered and should last a week or so. One problem would be that it cannot be in the cockpit and would be liable to theft.

Eventually, the dry air would find its way to all parts of the engine - even past piston rings.

Any views?
 
Fly your plane more! If not, find a way to make it get flown more. There are a couple of ways of doing this, most of which help offset ownership expenses. I had a deal with the owner of the Mooney I used to fly as he wasn't using it enough.

Doesn't answer your actual question (and I don't have a good answer for it), but planes don't belong in hangars. :)
 
Copper sulfate is white when dry, blue when moist. Bake it to dry it. Put it in a container with two hoses.. one hose is the air intake to the device.. the other hose connects to your oil filler (or dipstick ).. as the freshly run engine cools it draws air in through the device.. the air passing through the device is much much drier than ambient.

An example of a suitable container for hangar use would be a 3 liter soda bottle with the wider mouth. Punch two holes in lid for tubing.

To "recharge" take the moistened blue copper sulfate and bake it to above 109 degrees celsius (pretty much anything above 250 F) til it changes color.. and it loses 80 percent of its moisture content. You have to hit about 200 Celsius to get that last lil bit out..
 
OK, interesting, so it has been done before ;)

I like the acquarium pump :)

But nobody seems to have done a purely battery operated version. If you have mains power around to drive the acquarium pump, other solutions are possible, like a small dehumidifier generating dry air for the engine and the cockpit.
 
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