Is it really bad to leave the engine heater plugged in 24/7?

Capt. Geoffrey Thorpe said:
How many days/ weeks/ months does it take to evaporate and diffuse all of the moisture out a skinny little tube that is several feet long? There is a lot of water inside the engine.
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I don't care, as long as it goes OUT instead of onto the surfaces inside the engine.

And honestly, I don't think it's really that long. Our air is VERY cold and dry in the winter. I open the oil filler tube as soon as I exit the plane after shutdown, and you can see the engine's breath. ;) By the time I get the hangar open and the plane pushed back in, you can't. There's a pretty extreme difference in both temperature and humidity and there's a through path, so convection should clear it out fairly quickly.
 
Yes, it's a fire hazard. Why risk destroying your plane and hangar to save a few bucks?


Ron Levy said:
Any comments from the experts on using a warm air blower like this with a piece of aluminum ducting into the bottom of the cowl blowing relatively dry 75F air into the engine compartment all the time?
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On 24/7 below 30f for 15 years. Baths the engine in warmth. Keeps the oil around 60f. Perfect. Works for me. Doesn't travel well though. :rolleyes:
 
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JHW said:
blankets with characters from warm climates work better. The Dora the explorer blanket is the best you can get.
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No pics but old sleeping bags from the thrift store work very well, too.
 
Ron Levy said:
Gets it warmer, according to the JPI in my current non-Tanis Tiger versus the JPI in my former Tanis-equipped Cheetah. If I set it right, the oil and CH temps will be up in the 70's at even about a 4/10 heat setting on the blower. Also, purchase and installation of a Tanis or Reiff pad/cylinder system costs about eight times what this baby did.
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Put a blanket over your engine with the Tanis (which is the right way to do it) and your temps will be way higher. The 310 is warm enough that the oil temps are in the green and it needs a hot start technique.
 
steingar said:
Many desiccants change color once they're charged with liquid. Can you tell if the dehumidifier is actually absorbing anything?
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A conventional dehumidifier spits out the water it's removed from the air.
 
Ted DuPuis said:
Put a blanket over your engine with the Tanis (which is the right way to do it) and your temps will be way higher. The 310 is warm enough that the oil temps are in the green and it needs a hot start technique.
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75F is the green arc in my plane, and if I set the heater right, it will be there even without a blanket (but it's easier with).
 
LDJones said:
No pics but old sleeping bags from the thrift store work very well, too.
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Old horse winter turnout blankets work better. The neck hole fits right around behind the prop and covers the cowl openings and the chest fasteners hold it on there snug. A couple bungees to connect the belly straps and it's every bit as good as a Tanis blanket.

My setup is in the Geico & Ron Levy school.
 
steingar said:
Many desiccants change color once they're charged with liquid. Can you tell if the dehumidifier is actually absorbing anything?
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Mine works like an air conditioner, it lowers the temp and removes water vapor from the air and them pumps it into the engine.

Here is a link to their website.

http://www.enginesavers.com/

The only problem I have is in the winter it will freeze, so I put it in a Colman cooler and I just prop the lid open. It makes enough heat in the cooler to keep everything above freezing.

Flav
 
I use the Reiff system(cylinders and sump) and plug it in the night before planned flight; also, cowl plugs and sleeping blanket-type material over the cowl. If unintentionally left connected(planned flight not taken), electricity cost is a killer when compared to prudent use(my hangar, electricity on my coin). Bob Reiff told me to NOT use 24/7 UNLESS the plane shall be flown nearly daily, as might be the situation re flying club or rental planes.

HR
 
Kent: During an occasion when a March flight was WX postponed(for a week), I forgot to disconnect the Reiff. When the electricity bill next came my usual 1.5 to 2.0kh per month usage zoomed to over 125kw. It also happened the next month because the "service months" end/begin occurred in the middle of that one week period. Said mistake has not reoccurred.

HR
EDIT: However, in the pictured sequence, preheat wasn't necessary. For 4 months of winter the plane was in a hangar built for USN Orion P-3c(and its intended replacement) aircraft. 0* outside, no sweat inside the huge heated hangar. Often parked quite near it were Gulfstream, Lear, Citation(usually charter a/c there for a night or two, as in the Gulfstream whose owners/pilot brought the daughter and her friends back to Bowdoin College after spring break).
 

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nrpetersen said:
Remember - The corrosion rate doubles every 18 degF you raise the temperature.
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Again, only if all else is equal. By encouraging moisture to escape from the engine and not be on the engine's internal surfaces, I think I'm more than making up for the higher temperature.
 
flyingcheesehead said:
Again, only if all else is equal. By encouraging moisture to escape from the engine and not be on the engine's internal surfaces, I think I'm more than making up for the higher temperature.
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Agreed.....

To be clear,,, my motor has a crackcase vent on the valve cover and it is located on the highest part of the motor... It is NOT like a standard aircraft motor..:nonod:
 

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flyingcheesehead said:
Again, only if all else is equal. By encouraging moisture to escape from the engine and not be on the engine's internal surfaces, I think I'm more than making up for the higher temperature.
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I agree. Best would be before the engine cools down after landing. Aircraft engines would really benefit from positive crankcase ventilation - (like cars have for the last 40 years). I wonder why they don't?
 
nrpetersen said:
I agree. Best would be before the engine cools down after landing. Aircraft engines would really benefit from positive crankcase ventilation - (like cars have for the last 40 years). I wonder why they don't?
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Because it would probably cost 20 million to get it FAA certifed....:mad2:
 
nrpetersen said:
I agree. Best would be before the engine cools down after landing. Aircraft engines would really benefit from positive crankcase ventilation - (like cars have for the last 40 years). I wonder why they don't?
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PCV is an emission control. No engine "benefits" from PCV it is bad for the engine in every way. On the engines we build, we never install PCV where it is not required.
 
JHW said:
PCV is an emission control. No engine "benefits" from PCV it is bad for the engine in every way. On the engines we build, we never install PCV where it is not required.
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Except that it keeps the crankcase / oil clean and dry and makes engines last much longer. But. other than that, there is no benefit. And, I can sludge up the throttle body which will take 10 or 15 minutes to clean.
 
Capt. Geoffrey Thorpe said:
Except that it keeps the crankcase / oil clean and dry and makes engines last much longer. But. other than that, there is no benefit. And, I can sludge up the throttle body which will take 10 or 15 minutes to clean.
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no, it does the opposite. It retains water and chemicals inside the engine which would otherwise be purged overboard, making the oil both wetter and more acidic. it also leaves recidue in intake components, reduces life of many sensors, and increases crankcase pressure on some engines leading to more leaks.

other than that, yeah it's great:rolleyes:
 
JHW said:
no, it does the opposite. It retains water and chemicals inside the engine which would otherwise be purged overboard, making the oil both wetter and more acidic. it also leaves recidue in intake components, reduces life of many sensors, and increases crankcase pressure on some engines leading to more leaks.

other than that, yeah it's great:rolleyes:
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Yeah, I vent to atmosphere, especially on boosted engines.
 
JHW said:
with the heater plugged in the oil is the warmest part, the camshaft (in the case of a lycoming) the coldest. water is driven out of the oil as you heat it.

How, these heaters do not get hot enough to boil the water. The water will sink to the bottom of the oil and set there.

That means you have a saturated water vapor solution in the air immediately above the oil. That water will condense out somewhere else. Since the solution is saturated at the bottom and there is some non-zero temperature gradient throughout the engine, condensation somewhere is 100% guaranteed.

For people unable to accept basic thermodynamics it is easy anough to prove. Plug in the heater for a couple days and then take off a rocker shaft cover. You will find the inside of the metal cover covered with a fine mist of water. That is what most of the inside of your engine looks like.
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that water you see in the valve covers occurs while flying. NOT as it cools.

I get water in the engines on the test cell. yes the ones that have been freshly overhauled and have only test cell time.
 
Tom-D said:
that water you see in the valve covers occurs while flying. NOT as it cools.

I get water in the engines on the test cell. yes the ones that have been freshly overhauled and have only test cell time.
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water doesn't only sit on the bottom of the oil, there is water in suspended in the oil that constantly comes out and goes back in. As you heat it you drive more out. The phrase that oil and water don't mix is a lie. they don't mix like sugar and water, but oil does indeed hold water in solution.
 
JHW said:
water doesn't only sit on the bottom of the oil, there is water in suspended in the oil that constantly comes out and goes back in. As you heat it you drive more out. The phrase that oil and water don't mix is a lie. they don't mix like sugar and water, but oil does indeed hold water in solution.
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Yup... Ever seen water comtaminated oil.... it looks like Lubriplate grease...:eek::yikes:...... And it is NEVER good news...:nonod:.....:sad:
 
JasonM said:
I know a few guys that leave theirs plugged in during the winter. I met one that told me to plug it into a thermostat so it only comes on if the hanger gets below 50 deg or so. I also know a few that are telling me not too. Is this another one of those "who the hell really knows" deals?

I have always left the engine heaters on farm tractors during the winter and they always start easier with them on.

Is there any real proof of this causing damage to the engine? Is this something that would make flight risky if there was condensation?
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Engine heaters are for one purpose and one purpose only, to allow easier starting in cold temps.

And that's all they do.

It's your choice do you want to pay the electrical bill just to keep your engine at a constant temp.

Or would you simply like to heat your engine and go fly?
 
JHW said:
water doesn't only sit on the bottom of the oil, there is water in suspended in the oil that constantly comes out and goes back in. As you heat it you drive more out. The phrase that oil and water don't mix is a lie. they don't mix like sugar and water, but oil does indeed hold water in solution.
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It won't when the engine is not running. and if it is, the water will soon boil out.
 
JHW said:
no, it does the opposite. It retains water and chemicals inside the engine which would otherwise be purged overboard, making the oil both wetter and more acidic. it also leaves recidue in intake components, reduces life of many sensors, and increases crankcase pressure on some engines leading to more leaks.

other than that, yeah it's great:rolleyes:
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That is contrary to everything that I have learned from the GM engineers who were actually involved in testing the original PCV systems in the late '50s (Yes, it was before my time) for the effects on engine durability. According to them, PCV was one of the best things to ever happen for engine durability. But, what would they know, right? They just actually did the testing.
 
Capt. Geoffrey Thorpe said:
That is contrary to everything that I have learned from the GM engineers who were actually involved in testing the original PCV systems in the late '50s (Yes, it was before my time) for the effects on engine durability. According to them, PCV was one of the best things to ever happen for engine durability. But, what would they know, right? They just actually did the testing.
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I wonder if it might not have to do with differences between what are primarily naturally aspirated spark ignition engines vs. what are primarily turbocharged diesel engines.
 
Ted DuPuis said:
I wonder if it might not have to do with differences between what are primarily naturally aspirated spark ignition engines vs. what are primarily turbocharged diesel engines.
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Turbo Diesels? Whole 'nuther animal I would think.

A naturally aspirated gasoline engine has vacuum to keep fresh air constantly flowing through the crankcase. In automotive applications the PCV flow almost always exceeds the blowby so the moisture levels in the crankcase is kept down. At one point I found a paper with data on water / other stuff levels at various sample points and various speed loads on a PCV equipped engine - you could see the difference when the blowby overwhelmed the PCV flow into the intake.

Aircraft applications (particularly turbo) wouldn't get fresh air in during climb and not much during cruise - you would rely on descents and taxi time to clean out the crankcase. I have no data on how effective it would or would not be.

I'm not sure how they set up PCV on turbo diesels. Just diverting the flow to prevent it from getting out to the atmosphere would not be good - you really need the fresh air flow into the engine to move the garbage out.
 
Capt. Geoffrey Thorpe said:
That is contrary to everything that I have learned from the GM engineers who were actually involved in testing the original PCV systems in the late '50s (Yes, it was before my time) for the effects on engine durability. According to them, PCV was one of the best things to ever happen for engine durability. But, what would they know, right? They just actually did the testing.
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Well the kid (kid to me but he is 40-something) has engineered engines of types petrol, natural gas, and diesel, while working at GM, BMW, and Cat. Maybe he has some insight that runs counter to views of 60 years ago.
 
Capt. Geoffrey Thorpe said:
Aircraft applications (particularly turbo) wouldn't get fresh air in during climb and not much during cruise - you would rely on descents and taxi time to clean out the crankcase. I have no data on how effective it would or would not be.
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I've always assumed a PCV system would be worthless in aircraft applications for multiple reasons, but primarily due to a lack of vacuum.

Capt. Geoffrey Thorpe said:
I'm not sure how they set up PCV on turbo diesels. Just diverting the flow to prevent it from getting out to the atmosphere would not be good - you really need the fresh air flow into the engine to move the garbage out.
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It's simple, they don't. The newer engines we've built at work have an air/oil separator on them but the crankcase vent is still going to atmosphere. I think PCV would be a challenge to set up and have it be effective on an engine that basically creates no vacuum.
 
mondtster said:
I've always assumed a PCV system would be worthless in aircraft applications for multiple reasons, but primarily due to a lack of vacuum.
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why do you believe aircraft engines like we see today don't have vacuum?
 
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