Can engine heater reduce/prevent engine corrosion?

[DanStrange]

Whoever pointed to Mike Busch's article, thank you. Here is the article:
https://www.avweb.com/ownership/the-whys-and-hows-of-preheating/

Here is the relevant part (I bolded the important parts):
"Leave it on all the time?
There has been considerable controversy about whether or not it’s a good idea to leavean electric preheating system plugged in continuously when the airplane isn’t flying. BothTCM and Shell have published warnings against leaving engine-mounted electric preheaterson for more than 24 hours prior to flight. However, these cautions are really applicable primarily to single-point heaters such as oil pan heaters. The concern of TCM and Shell is that heating the oil pan will cause moisture toevaporate from the oil sump and then condense on cool engine components such as thecamshaft, crankshaft or cylinder walls, resulting in accelerated corrosion of those parts. However, if the entire engine is heated uniformly by means of a multipoint heating system,or because the engine and propeller are covered with insulated engine and prop covers, such condensation is very unlikely to occur.

In fact, using an insulated cover and a multipoint preheating system that is plugged in continuously is one of the most effective methods of eliminating internal engine corrosion, particularly if the aircraft is kept in an unheated hangar rather than outdoors. If the entire engine is maintained above the dewpoint, condensation simply cannot occur"

I am going to plug in my pre-heater and keep it on 24/7.
Thank you everyone!

Even though the instructions from the manufacturer of the engine say not to?

I would follow the people who made the engines advice over some self proclaimed internet expert.

Or ask people with revenue generating planes in the area what they do.

 

[EdFred]

Mike Busch has been running snake oil in his engines rather than 20W50 or 100W. Cheaper when you're the distributor.

I guess if you look long enough on the internet for the answer you want you can get it. Evidently conduction doesn't exist in Busch's world.

 

[chemgeek]

For condensation to occur, there has to be available moisture, and a local temperature lower than the dew point. In the winter months, an aircraft stored in a hangar is likely well above the dew point as the ambient air will be quite dry. The temperature inside a hangar, even an uninsulated one, will normally be higher than the outdoor temperature, lowering the RH and raising the dew point compared to outdoor air. Unless there is a source of excess moisture inside the hangar (snow melt, rain ingress), atmospheric condensation is likely to be minimal. The other reservoir of moisture, other than ambient air, is the engine oil. Heating it could drive residual moisture out, raising the RH inside the engine, and lead to condensation on colder parts. But the reservoir of moisture in the engine oil is likely quite small. The reality it that is probably doesn't matter much whether you heat your oil or not to prevent engine corrosion. If you want to keep the engine from internal corrosion, the best thing to do is to fly it regularly. I've never seen condensation or frost inside my hangar, absent a flood under the hangar door. Heating your oil does make the engine easier to start and reduces wear during cold starts.

 

[OneCharlieTango]

There's no doubt that continuous warming almost always keeps the internal temperature above the dew point. It doesn't necessarily follow that corrosion becomes impossible. Corrosion is almost certainly possible without liquid water. And heat accelerates all chemical reactions including oxidation.

But maybe none of this matters either. It's a complicated topic. The answers are probably more determined by the specifics of location, hours of sunlight, hangar insulation, high-low temperature swings, age of the pilot, age of the pilot's neighbors. . . .

 

[Stewartb]

For condensation to occur, there has to be available moisture, and a local temperature lower than the dew point. In the winter months, an aircraft stored in a hangar is likely well above the dew point as the ambient air will be quite dry. The temperature inside a hangar, even an uninsulated one, will normally be higher than the outdoor temperature, lowering the RH and raising the dew point compared to outdoor air. Unless there is a source of excess moisture inside the hangar (snow melt, rain ingress), atmospheric condensation is likely to be minimal. The other reservoir of moisture, other than ambient air, is the engine oil. Heating it could drive residual moisture out, raising the RH inside the engine, and lead to condensation on colder parts. But the reservoir of moisture in the engine oil is likely quite small. The reality it that is probably doesn't matter much whether you heat your oil or not to prevent engine corrosion. If you want to keep the engine from internal corrosion, the best thing to do is to fly it regularly. I've never seen condensation or frost inside my hangar, absent a flood under the hangar door. Heating your oil does make the engine easier to start and reduces wear during cold starts.

Do you have any experience with engine tear-down in a heated hangar in winter? My experience with tearing down my own engines is vastly different than what you stated. And I applaud the comment that there are regional considerations to take into account. Still, more guys should dig into the issue. This discussion would take a different path. Water is present inside most of your engines when hangar parked. You assume the relative humidity inside your engine is equal to that in the hangar. That's incorrect. It's usually much higher. Adding heat doesn't drive moisture out. It may return it to a gaseous state, until it finds a place to condense again, like in cylinder heads.

 

[chemgeek]

There's no doubt that continuous warming almost always keeps the internal temperature above the dew point. It doesn't necessarily follow that corrosion becomes impossible. Corrosion is almost certainly possible without liquid water. And heat accelerates all chemical reactions including oxidation.

But maybe none of this matters either. It's a complicated topic. The answers are probably more determined by the specifics of location, hours of sunlight, hangar insulation, high-low temperature swings, age of the pilot, age of the pilot's neighbors. . . .

If by heating the oil you drive out water vapor suspended in it, the relative humidity inside the engine could be quite high, while the exterior of the engine remains above the dew point of ambient air on the exterior of the aircraft. It's not the ambient air that is of concern, it's the air inside the engine. But I suspect that it is neither here nor there if a plane is flown often enough to drive much of the moisture out of the oil and off the internal engine parts. Heating the oil will, however, do nothing to deal with accumulated acids in the oil itself, most of which are not volatile enough to be driven off by an oil heater. Heating will only accelerate the chemical reaction between those weak acids and internal metal parts.

 

[MacFly]

I have been through this many times and it gets tedious so end of discussion for me.

You're first person I've EVER heard that would try to assert that cold-starting on an aircraft engine isn't damaging. I'm sure you're a smart guy and all of that, but I'm gonna go with recognized experts rather than SGOTI. Your Porsche anecdote isn't the same thing as "data".

 

[David Megginson]

No, it's the same type of engine using the same aluminum and steel . The Porsche 911 engine was used in, I think, Mooneys.

Oil film strength is quite high and the colder the stronger. A different rate of thermal expansion does occur between the aluminum crankcase and the steel crankshaft but not between the steel crankshaft and the steel connecting rods so, if this were a real problem, we would regularly see scored main bearings but not scored rod bearings in the same engine. Therefore, the oil film strength must use the elasticity of the crankcase to prevent metal to metal contact. Another way you can test this is to see if you can hand turn the prop at very cold temps. If you can then it's not metal to metal.

I have been through this many times and it gets tedious so end of discussion for me.

Here's some reading, if you want to get your info from a specialist instead of people like me.

https://www.aopa.org/news-and-media...lot/savvy-maintenance-crimes-and-misdemeanors

Interesting side note from the article: new cylinders are at much bigger risk than old, worn ones, because the tolerances are tighter.

 

[David Megginson]

Whoever pointed to Mike Busch's article, thank you. Here is the article:
https://www.avweb.com/ownership/the-whys-and-hows-of-preheating/

Here is the relevant part (I bolded the important parts):
"Leave it on all the time?
There has been considerable controversy about whether or not it’s a good idea to leavean electric preheating system plugged in continuously when the airplane isn’t flying. BothTCM and Shell have published warnings against leaving engine-mounted electric preheaterson for more than 24 hours prior to flight. However, these cautions are really applicable primarily to single-point heaters such as oil pan heaters. The concern of TCM and Shell is that heating the oil pan will cause moisture toevaporate from the oil sump and then condense on cool engine components such as thecamshaft, crankshaft or cylinder walls, resulting in accelerated corrosion of those parts. However, if the entire engine is heated uniformly by means of a multipoint heating system,or because the engine and propeller are covered with insulated engine and prop covers, such condensation is very unlikely to occur.

In fact, using an insulated cover and a multipoint preheating system that is plugged in continuously is one of the most effective methods of eliminating internal engine corrosion, particularly if the aircraft is kept in an unheated hangar rather than outdoors. If the entire engine is maintained above the dewpoint, condensation simply cannot occur"

I am going to plug in my pre-heater and keep it on 24/7.
Thank you everyone!

Thanks for sharing that. I'm not sure about everyone else, but when I write about preheating, I always mean a proper, multipoint system like the Tanis, not just a heating pad stuck to the bottom of the oil sump (or worse, a 100 watt utility light under the cowling). The old pilot myth was that the problem with a cold start is thick oil. That might be true of single-grade oils in the Arctic at -40c, but at more moderate temperatures like -10c, multi-grade oil will still happily flow through the engine without preheating. What we really need to preheat is the cylinders, not the oil pan (though I have both in my PA-28-161).

 

[DanStrange]

You're first person I've EVER heard that would try to assert that cold-starting on an aircraft engine isn't damaging. I'm sure you're a smart guy and all of that, but I'm gonna go with recognized experts rather than SGOTI.

Depends on cold.

If it’s engineer guy grabs Patagonia vest cold, probably ok

If it’s farmer grabs big carhart and muck boots, preheat time

Or just ask the people who invented your engine
http://reiffpreheat.com/Continental SIL 03-1 Cold Wx Ops.pdf

Do not leave an engine-mounted pre-heater system on for more than twenty- four hours prior to flight. Continuous operation of engine-mounted preheater systems may result in aggressive corrosive attack internal to the engine.

Preheating is required whenever the engine has been exposed to temperatures at or below 20° Fahrenheit / - 7 degrees Centigrade (wind chill factor) for a period of two hours or more.

 

[David Megginson]

Depends on cold.

If it’s engineer guy grabs Patagonia vest cold, probably ok

If it’s farmer grabs big carhart and muck boots, preheat time

Or just ask the people who invented your engine
http://reiffpreheat.com/Continental SIL 03-1 Cold Wx Ops.pdf

It depends on where the engineer or farmer lives, I guess. Here in Ottawa, it gets down as cold as -35c (windchill below -40c) some winter days, then as high as +5c others. On the cold days, an engineer in Ottawa wouldn't make it from their car to their office in a flimsy little vest. But while, with multigrade oil at least, our engines will still crank at moderate temperatures like -10c (I've done it in a pinch to avoid being stuck at a remote field when the FBO couldn't preheat for me), it's a really bad idea to make a habit of it unless getting frequent top overhauls is your special hobby.

p.s. While the local flying school suspends ops at -25c, I have flown my PA-28-161 down to -30c on the ground and -35c OAT at altitude. The cabin heat can just about keep up, except when the sun goes behind a cloud. And yes, I had proper boots, face covering, and lots of layers on, so that I could stay alive for a few hours after a forced landing. It's not the Arctic around here, but still, real cold (not mid-Atlantic "OMG! A snowflake!" cold) isn't foreign to us.

 

[A Martin]

~~

Most people do not realize that engine corrosion is very seldom related to the crankcase or crankcase oil.

Daily breathing experienced by a parked engine is through the open intake and open exhaust valves .... there are always several valves open or partially open when an engine is not running.

And because the combustion chamber , upper cylinders , and piston rings have very little oil film to begin with ... they will be more susceptible to moisture in the air that moves in and out .... day and night , winter and summer.

To make matters even worse if shutdown is done by shutting off magnetos the engine will continue to turn several times which draws in un-burned fuel which will wash away the tiny bit of oil that had been on the piston rings.

I have seldom seen corrosion in a crankcase or oil pan .... it is always seized pistons , rings , and valve stems.

 

[MountainDude]

Mike Busch has been running snake oil in his engines rather than 20W50 or 100W. Cheaper when you're the distributor.

I guess if you look long enough on the internet for the answer you want you can get it. Evidently conduction doesn't exist in Busch's world.

Can you please tell me what conduction is and which Mike's statements are wrong? Thank you

 

[DanStrange]

Can you please tell me what conduction is and which Mike's statements are wrong? Thank you

Not me, but the statement the blogger made contradictory to the manufacture of the engine, where the blogger said to leave it plugged in

 

[A Martin]

Most gall occurs on a cold engine at startup

Gall is a term to describe wear , chaffing , loss of metal , between 2 moving parts.

Gall happens on cold metal (cold engine) (startup)

A constantly running warm engine with an oil film will never experience gall and will run practically forever . That same engine stopped & started (cold) every day will wear out much faster.

That is the main reason preheating a cold engine is beneficial .... gall likes cold metal .

And of course warm oil circulates better , less raw fuel required to prime ,.

Raw fuel to start a cold engine washes away any trace of upper cylinder engine oil and gall has a lengthy feast before engine and oil has warmed up enough to provide a lubricating film.

Thus the old saying .... most engine wear occurs at startup

 

[EdFred]

Can you please tell me what conduction is and which Mike's statements are wrong? Thank you

conduction:
the process by which heat or electricity is directly transmitted through a substance when there is a difference of temperature or of electrical potential between adjoining regions, without movement of the material.

I guess in Mike's world a container can never get hot if the liquid inside of it is heated from a single point. Pretty much have to discard everything he vomits after that. Go ahead grab that deep fryer with your bare hands.

 

[A Martin]

More trivia regarding moisture in the air , corrosion , and cold or warm metal.

I spent 30 years as a professional painter and was often asked why white cars rust more than black cars.

Middle of the winter .... coldest day .... put your hand on a black car and it will be much warmer than the surrounding air (solar heat)

Any moisture will move from the warm metal to the cold air and the black surface will be dry.

Hottest day of the year place your hand on a white car and it will be cool

Moisture in the warm air will move to the cooler white surface and promote corrosion.

 

[Tom-D]

We all know there is water in our crankcases But what happens to it when the engine stops.
as the steam coverts into the droplets it will adhere to the coldest parts in the engine.
we all know that water is heavier than oil and will settle into the lowest part of the sump.
As the water settle it will separate from the oil, causing the water to be contain in the sump and be separated but not protected from corrosion of the sump.

 

[Snowmass]

Most gall occurs on a cold engine at startup
That is the main reason preheating a cold engine is beneficial .... gall likes cold metal .

Which is why a hundred million Americans preheat their autos every morning at temperatures below 40F. Gall could not care less about metal temperatures. Gall likes oil film breakdown when oil is to thin to prevent metal to metal.

 

[Matthew Rogers]

Well autos today also use 0w super thin synthetic oil and are driven usually multiple times every day. So the parts are always freshly oiled, the oil flows super fast on startup even when freezing, and the synthetic oil sticks and protects better than Dino oil.

Can’t be thin oil causing damage on its own because autos use super thin oil and airplane use super thick oil and we still have problems with the airplane engines while the cars work just fine at all temps with no special care given.

 

[Stewartb]

A- according to my car manuals preheat isn't necessary until WELL below zero. Plugging in is about reducing idle warm-up time and that's an air quality issue. Those of us who live where it's cold know about winter air quality.

B- cars use positive crankcase ventilation and other tricks that keep corrosives minimized.

Reduction of corrosives is one reason I'm using a crankcase vacuum system on my Cub.

 

[danhagan]

Accepting that after you fly, there will be some water in the oil, and the air in the crankcase will be quite humid due to blow by.

My plan is to run the heater all the time, but leave the dipstick out...

We all know there is water in our crankcases But what happens to it when the engine stops. as the steam coverts into the droplets it will adhere to the coldest parts in the engine.

I'm in the desert, so this may not due squat to help. A couple of years ago I gave a ride to a local here that has a ton of experience with engines (aviation, sprint cars, competitive dirt bikes etc.). Prior to landing we had had this discussion and he asked if he "could show me something" at shutdown. Immediately after shutdown he had me pull the dipstick back about 8 inches and the amount of steam escaping was pretty impressive. Not sure if it does anything at all, but I now do this after shutdown, push the plane into the hangar, scrub bugs and clean the windshield, put the canopy and wing covers on for dust ... total time about 20-30 minutes, then re-insert dip stick. I know it is upper engine vapor-water only, but I guess it helps somewhat ...

 

[kyleb]

I know it is upper engine vapor-water only, but I guess it helps somewhat ...

I'm sure it helps some. But that dipstick tube ends at the sump, so I'm not sure your thoughts on "upper engine" are correct. I'd just say you're exhausting moisture and be happy with that.

 

[Tom-D]

I'm in the desert, so this may not due squat to help. A couple of years ago I gave a ride to a local here that has a ton of experience with engines (aviation, sprint cars, competitive dirt bikes etc.). Prior to landing we had had this discussion and he asked if he "could show me something" at shutdown. Immediately after shutdown he had me pull the dipstick back about 8 inches and the amount of steam escaping was pretty impressive. Not sure if it does anything at all, but I now due this after shutdown, push the plane into the hangar, scrub bugs and clean the windshield, put the canopy and wing covers on for dust ... total time about 20-30 minutes, then re-insert dip stick. I know it is upper engine vapor-water only, but I guess it helps somewhat ...

I always did too.
0-300 / 0-200 have large opening, and the steam is apparent .

 

[David Megginson]

conduction:
the process by which heat or electricity is directly transmitted through a substance when there is a difference of temperature or of electrical potential between adjoining regions, without movement of the material.

I guess in Mike's world a container can never get hot if the liquid inside of it is heated from a single point. Pretty much have to discard everything he vomits after that. Go ahead grab that deep fryer with your bare hands.

Busch does not recommend leaving cheap, single-point oil-sump heaters plugged in 24/7 either; he recommends it only for multi-point heaters like the Tanis, where there is a heating probe sticking into each cylinder as well as a pad under the oil. I can't remember if he mentions this, but Tanis also recommends always using an insulated cover so that the heat spreads evenly through the whole engine compartment (starting from inside the cylinders and spreading outwards).

This morning, with an OAT of 6c, my entire engine (Lycoming O-320-D3G on a PA-28-161) was warm to the touch — hard to say exactly how warm, but at least 30-40c (on a cold winter day, it would be more like 20c). The covers over my canopy and tailcone were damp, but the inside of the engine compartment -- including the inside of the cowl and the firewall -- was bone dry. The insulated cover over the cowling was also dry, unlike the other covers, because the heat coming from underneath it was enough to keep it that way.

I don't have a propeller cover yet, but it's on order from AeroCovers (a great Canadian company that I've been doing business with for 18 years).

 

[David Megginson]

A- according to my car manuals preheat isn't necessary until WELL below zero. Plugging in is about reducing idle warm-up time and that's an air quality issue. Those of us who live where it's cold know about winter air quality.

B- cars use positive crankcase ventilation and other tricks that keep corrosives minimized.

Reduction of corrosives is one reason I'm using a crankcase vacuum system on my Cub.

I never preheat my car these days — my Mazda 3 will still cold-start fine at -35c (a bit of growling, but it turns over).

Back in the 1960s and 70s, though, nearly very car engine around here (central Canada) had a block heater with an electrical cord poking out of the front grille, and many public parking spots -- even outdoor ones -- had outlets for them. You just wouldn't have much luck starting many cars once it got cold out. Our airplane engines have more in common with 1970s automotive technology (well, maybe 1940s) than with contemporary engines.

 

[MacFly]

I have the silica bead one and it’s not that bad. I bought extra beads and just swap them out every month.


http://www.reiffpreheat.com/Article-Sutton.pdf

https://www.aviationconsumer.com/maintenance/engine-dehydrators-engine-saver-prevails/

I built a dehydrator out of an airtight Rubbermaid dog food container, some clear bubble tubing, a $15 aquarium pump, and 7.5 lbs of silica gel beads. A #6 rubber stopper with a hole in it for the inlet tubing fits a Lycoming IO-320-D1A dipstick tube perfectly. It’s been running about 1 week and I haven’t had a catastrophic engine failure yet, and no signs of any corrosion . I have humidity gauges (like...$4 at Amazon) in the silica tank and on the outside. Today I noted the humidity outside (ambient air) registered 57% while the air I was pumping into the crankcase (post-silica) was at 14%.

 

[WannFly]

Throwing In some data point from flight today. Reiff turbo xp multi point heater plugged in for over 24 hrs. Engine cover not yet on, it’s too warm for that ha.

Wind chill factor 26 F. Upon starting oil temp was 118 degrees and all cylinders were between 110-140

My plane manufacturer also said to only lean at 5000 feet. That’s a load of poop. Engine only cares about DA - so when conti says don’t plug in for more than 24 hrs let’s find out when the article was written and in which context.

As I said before, out here, if people are flying the plane is plugged in all winter, for years and none of them have dropped out of the sky yet.

 

[MacFly]

Wind chill factor 26 F. Upon starting oil temp was 118 degrees and all cylinders were between 110-140

I would note (not saying you don’t know this) that wind chill has nothing to do with actual engine temp. The engine will never be colder than ambient temp. Wind chill is irrelevant.

 

[WannFly]

I would note (not saying you don’t know this) that wind chill has nothing to do with actual engine temp. The engine will never be colder than ambient temp. Wind chill is irrelevant.

Yup, I am aware, someone mentioned wind chill factor above, hence my comment. To put some more perspective, temp was 35 when I took off, dew point 16.

 

[OneCharlieTango]

I would note (not saying you don’t know this) that wind chill has nothing to do with actual engine temp. The engine will never be colder than ambient temp. Wind chill is irrelevant.

Wind chill matters in terms of conductive heat loss, right? Just like your furnace runs more on a cold, windy day than it does on a cold, calm day.

 

[Kevin Eggert]

There is zero correalation between an engine heater and reduced corrosion. If anything, the heater will only promote corrosion. The purpose of an engine heater is to promote quick pumping of oil throughout the engine in order to properly and effectively lubricate metal on metal parts. The only way to prevent corrosion is to reduce or eliminate moisture in the air or by coating parts with oil to prevent the contact of moisture within the engine cavities. Heating will absolutley not accomplish this. In fact, it does just the opposite, by vaporising any moisture that may be trapped in liquid form in the oil and vaporize it into the open cavities of the engine. Dehumidification or coating is the only solution to corrosion and has no correlation to the heating of oil.

 

[David Megginson]

There is zero correalation between an engine heater and reduced corrosion. If anything, the heater will only promote corrosion. The purpose of an engine heater is to promote quick pumping of oil throughout the engine in order to properly and effectively lubricate metal on metal parts.

Especially in the days of multigrade oil, the main purpose of a proper engine heater isn't to warm the oil (unless you're in the Arctic at -45c), but to warm the the engine so that pistons and bearings have proper clearance before things start moving. That's why warming the oil alone is dangerously inadequate:

https://www.avweb.com/ownership/the-whys-and-hows-of-preheating/

Keeping the inside of the engine and engine compartment dry during cold weather isn't the main reason for an engine heater, but it's a nice bonus.

 

[MacFly]

Wind chill matters in terms of conductive heat loss, right? Just like your furnace runs more on a cold, windy day than it does on a cold, calm day.

It matters in terms of convective heat loss, yes. That would mean, if your airplane was out in the wind, its temperature would drop more rapidly than if it was in your (unheated) hangar. It would still come down to the same temperature in either place, it would just get there faster out in the wind.

 

[Snowmass]

Especially in the days of multigrade oil, the main purpose of a proper engine heater isn't to warm the oil (unless you're in the Arctic at -45c), but to warm the the engine so that pistons and bearings have proper clearance before things start moving. That's why warming the oil alone is dangerously inadequate:

I have started my IO-520 many times at temps close to zero F with no preheat and have never encountered abnormal wear problems.(I have majored this engine twice myself.) Pre-heat is nice for batteries, starter motors and avoiding plug frosting but there is no PROOF that starting cold harms engines, just endless repeating of unproven claims. This is why I keep using the Porsche 911 engine is an example of a $40,000 engine constructed just like a GA engine (and is also a GA engine) and Porsche makes no mention of a pre-heat requirement. And I can assure you that these engines are started regularly sub-zero in Aspen CO.

 

[OneCharlieTango]

It matters in terms of convective heat loss, yes. That would mean, if your airplane was out in the wind, its temperature would drop more rapidly than if it was in your (unheated) hangar. It would still come down to the same temperature in either place, it would just get there faster out in the wind.

You're right; convective. Wind chill won't affect how cold an engine gets, but it can affect how warm it gets with a preheater.

 

[idahoflier]

I have started my IO-520 many times at temps close to zero F with no preheat and have never encountered abnormal wear problems.(I have majored this engine twice myself.) Pre-heat is nice for batteries, starter motors and avoiding plug frosting but there is no PROOF that starting cold harms engines, just endless repeating of unproven claims. This is why I keep using the Porsche 911 engine is an example of a $40,000 engine constructed just like a GA engine (and is also a GA engine) and Porsche makes no mention of a pre-heat requirement. And I can assure you that these engines are started regularly sub-zero in Aspen CO.

Just curious, did your engine and cylinders make TBO before both overhauls?

 

[A Martin]

I built a dehydrator out of an airtight Rubbermaid dog food container, some clear bubble tubing, a $15 aquarium pump, and 7.5 lbs of silica gel beads. A #6 rubber stopper with a hole in it for the inlet tubing fits a Lycoming IO-320-D1A dipstick tube perfectly. It’s been running about 1 week and I haven’t had a catastrophic engine failure yet, and no signs of any corrosion . I have humidity gauges (like...$4 at Amazon) in the silica tank and on the outside. Today I noted the humidity outside (ambient air) registered 57% while the air I was pumping into the crankcase (post-silica) was at 14%.

CLEVER ..... and that pump would only use a minuscule amount of power (esp compared to an engine heater)

I know railroads pass brake air (compressed air) through silica to remove moisture .... military used it to keep medicine and equipment dry and in gas masks to remove humidity

You say you are pumping air thru the dipstick tube and reducing humidity from 57 to 14% .... I wonder if you could find a second engine vent opening so you could recirculate that same 14% air back thru the silica .... could it not reduce moisture even more ? Just thinking out loud. I think your idea is great.

 

[kyleb]

You say you are pumping air thru the dipstick tube and reducing humidity from 57 to 14% .... I wonder if you could find a second engine vent opening so you could recirculate that same 14% air back thru the silica .... could it not reduce moisture even more ? Just thinking out loud. I think your idea is great.

Some of these systems use the breather for that purpose.

 

[MacFly]

CLEVER ..... and that pump would only use a minuscule amount of power (esp compared to an engine heater)

I know railroads pass brake air (compressed air) through silica to remove moisture .... military used it to keep medicine and equipment dry and in gas masks to remove humidity

You say you are pumping air thru the dipstick tube and reducing humidity from 57 to 14% .... I wonder if you could find a second engine vent opening so you could recirculate that same 14% air back thru the silica .... could it not reduce moisture even more ? Just thinking out loud. I think your idea is great.

Currently, the dry air I'm pumping in through the dipstick tube is just venting out to the atmosphere from the crankcase breather tube. My plan, when I get around to it, is to find a stopper that will fit my crankcase breather and run tubing from from it into a little food container that I'll put the little aquarium pump in. Then it will be the air from the crankcase that I'm pumping in instead of air from the atmosphere. Should save on silica.