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

But PCV would purge the crankcase of water vapor during a taxi-in. and there is still enough vacuum during cruise with a normally aspirated engine to minimize the moisture buildup in the crankcase.

Something has radically extended the useful life of automobile engines over the last 30 years. I attributed it to PCV and better air cleaners, but I'm a machine design engineer.
 
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Tom-D said:
why do you believe aircraft engines like we see today don't have vacuum?
Click to expand...

You will have little vacuum when flying. Idling and taxiing sure, but when you are at WOT or close to it there won't be much if any.
 
nrpetersen said:
But PCV would purge the crankcase of water vapor during a taxi-in.

Something has radically extended the useful life of automobile engines over the last 30 years. I attributed it to PCV and better air cleaners, but I'm a machine design engineer.
Click to expand...

Would your idle time really do enough good to consider it worth pursuing? (I've always assumed not)

Further, I'd rather not gunk up my induction system more than they already get.
 
Capt. Geoffrey Thorpe said:
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.
Click to expand...

I think that sounds right. In the experimental world, I've seen exhaust venturi-driven PCV setups that claim to make an improvement. I've never worked with them, and also haven't worked with something like what Ben uses.

For our old engines, even if there's new data, it's probably also on newer style engines. I could see benefits on our older style engines. Since we operate at full throttle most of the time, we'd need some sort of intake venturi to create a lower pressure to suck the crankcase. I'd personally be interested.
 
So, going back to the initial question...

If leaving the heater on 24/7 which raises the engine temp to, say 70 degrees is bad, do you guys have a giant walk in cooler to put your airplane in during the summer months when the ambient temp is 70 degrees? Jus' sayin'
 
EdFred said:
So, going back to the initial question...

If leaving the heater on 24/7 which raises the engine temp to, say 70 degrees is bad, do you guys have a giant walk in cooler to put your airplane in during the summer months when the ambient temp is 70 degrees? Jus' sayin'
Click to expand...

Exactly. And how many of us have corrosion in our car engines...
 
Ted DuPuis said:
Exactly. And how many of us have corrosion in our car engines...
Click to expand...

I know! I have to have my Vette engine overhauled every spring after it sits for the winter because of the massive corrosion that happens from not driving it. :rolleyes:
 
EdFred said:
I know! I have to have my Vette engine overhauled every spring after it sits for the winter because of the massive corrosion that happens from not driving it. :rolleyes:
Click to expand...
sheesh - I could store your vette here for maybe half what you are paying for the overhaul...maybe :rofl:
 
With the latest, early bout of Global Warming hitting most of the country, it's perhaps time for the annual resurrection of this thread.

My PA28 is hangared but unheated. It is a @*$&!!! to start when it's cold (like below 45deg.)

So here's what I'm thinking for a cheapskate heater: get a couple electric heating pads (like for your bad back) put one on each side of the engine (the upper cowling is hinged/split), put in the cowl plugs and wrap the cowling with a moving blanket. Maybe cover the prop as well since it's a big heat sink. Put the heaters on a "travel" timer set to come on at midnight and run until 9AM (to be determined experimentally). The engine should be toasty, or at least at room temperature, in the morning, right?

Any holes in this plan?
 
EdFred said:
So, going back to the initial question...

If leaving the heater on 24/7 which raises the engine temp to, say 70 degrees is bad, do you guys have a giant walk in cooler to put your airplane in during the summer months when the ambient temp is 70 degrees? Jus' sayin'
Click to expand...

In the summer, the rest of the engine block is 70-100 degrees also. Condensation doesn't form. The problem a partially cold engine block. The water vaporizes with the warmth of the heater, then condenses on the rest of the cold, unheated engine block.
 
paflyer said:
With the latest, early bout of Global Warming hitting most of the country, it's perhaps time for the annual resurrection of this thread.

My PA28 is hangared but unheated. It is a @*$&!!! to start when it's cold (like below 45deg.)

So here's what I'm thinking for a cheapskate heater: get a couple electric heating pads (like for your bad back) put one on each side of the engine (the upper cowling is hinged/split), put in the cowl plugs and wrap the cowling with a moving blanket. Maybe cover the prop as well since it's a big heat sink. Put the heaters on a "travel" timer set to come on at midnight and run until 9AM (to be determined experimentally). The engine should be toasty, or at least at room temperature, in the morning, right?

Any holes in this plan?
Click to expand...

Maybe holes in the airplane if it catches fire. I'm not sure i would leave anything not intended to be left on that long, .... on that long. i think there are warnings on alot of those heat pads about extended use.





update: Last winter I would leave my engine block heater on if I intended to fly at least once per week. This was most of the winter and everything worked out great. I will likely do the same this winter, but so far I have just turned it on the day before.



.
 
The colder it gets, the more I prime and mine starts o.k. but I'm not in real cold country.

It's a dilemma especially when you don't have block heat.

I don't like leaving anything on unattended because of the related risks, but if I had a block heater and it's sub freezing, I'd use it or at least try to pre-heat with it before a trip. There's gotta be a app for that .. :rolleyes2:
 
JasonM said:
Maybe holes in the airplane if it catches fire. I'm not sure i would leave anything not intended to be left on that long, .... on that long. i think there are warnings on alot of those heat pads about extended use.





update: Last winter I would leave my engine block heater on if I intended to fly at least once per week. This was most of the winter and everything worked out great. I will likely do the same this winter, but so far I have just turned it on the day before.



.
Click to expand...
I think the extended use refers to the human, not the pad.
 
Vacuum = Manifold pressure reading engine stopped - Manifold press engine running

My understanding of vacuum is the vacuum is the non altitude corrected barometric pressure (what your manifold pressure gauge reads before you start it) MINUS the manifold pressure you are reading with engine running. So if you are at 5000' and would have 25" of manifold pressure on the gauge when engine not running, AND you have WOT so have 24" showing on the manifold pressure gauge at WOT, you have 1" of vacuum (very little). Back off the throttle suddenly, and vacuum goes WAY up. Lug it up at a low rpm and max throttle, and you have very little.

Im no expert and wll admit being a little rusty on this one, but I think its right.
 
My first car was a 1951 Henry J with a vacuum powered windshield wipers. When you went up a hill, full throttle in third the wipers would almost stop (sometimes they would stop). Then when you get to the top of the hill and let off the gas, oh boy, they would go like CRAZY!
 
N801BH said:
My motor gets maximum vacuum at wide open throttle.. This works on ANY engine , turboed or not........

http://www.summitracing.com/parts/MOR-25900

And the belly stays squeaky clean too....:yes:;)
Click to expand...
Looks like what I run from the air oil separator into the exhaust:
http://antisplataero.com/Saddle_Mount___Valve.html
It will build carbon over time and there have been cases where carbon buildup has been suspected in pressurizing the crankcase resulting in front seal blowout / forced landing.
 
FORANE said:
Looks like what I run from the air oil separator into the exhaust:
http://antisplataero.com/Saddle_Mount___Valve.html
It will build carbon over time and there have been cases where carbon buildup has been suspected in pressurizing the crankcase resulting in front seal blowout / forced landing.
Click to expand...
To make the Moroso crankcase vacuum device work on my toy I use a rather large filtered breather in the left valve cover.... If the exhaust venturi carbons up, my motor will just breath out that valve cover filter... NO chance of hurting any seals...:no:
 
N801BH said:
To make the Moroso crankcase vacuum device work on my toy I use a rather large filtered breather in the left valve cover.... If the exhaust venturi carbons up, my motor will just breath out that valve cover filter... NO chance of hurting any seals...:no:
Click to expand...
On mine I have cut a slit in the hose between the air/oil separator and the exhaust valve.The slit is normally closed but acts as a blow off valve in event of pressure build up.
 
FORANE said:
On mine I have cut a slit in the hose between the air/oil separator and the exhaust valve.The slit is normally closed but acts as a blow off valve in event of pressure build up.
Click to expand...


Yup....

That will work...
 
paflyer said:
So here's what I'm thinking for a cheapskate heater: get a couple electric heating pads (like for your bad back) put one on each side of the engine (the upper cowling is hinged/split), put in the cowl plugs and wrap the cowling with a moving blanket. Maybe cover the prop as well since it's a big heat sink. Put the heaters on a "travel" timer set to come on at midnight and run until 9AM (to be determined experimentally). The engine should be toasty, or at least at room temperature, in the morning, right?
Click to expand...

Doubt it. Those pads don't get nearly as hot as, for example, the cylinder bands on a Reiff preheater. You're likely to end up with the top half of the engine/cylinders warmer than the bottom. Your oil will still be very cold and thick and not get to where it needs to be very fast (which is one of the primary reasons for needing to heat in the winter), and your cylinders will be heated unevenly and have increased wear.

It might be easier to start - or it might not - But that would be about the only "advantage" of heating it this way.

Don't be a cheapskate - The Reiff Standard System (which includes bands around each cylinder as well as an oil pan heater) is a whopping $435, with 2-4 hours of labor for installation. That's a tiny fraction of the cost of an engine overhaul.

The "cheap" methods for warming your engine in the winter are a false economy. There's no substitute for doing it right.

http://reiffpreheat.com/
 
I've got a Tanis which has pads on both the sump and the top of the case AND heaters on each cylinder. They have several different styles of cylinder heating element available. Mine are a small block that is held to the top of the cylinder by a screw through one of the rocker cover holes (it's narrower than the normal screw). Works great...

For control I used to have a combination unit that has a mechanical line voltage thermostat that I could set down to about 45 and a day of the week timer. Every Friday, Saturday, and Sunday morning if it was cold enough the heater came on at 2 AM so my early morning weekend departures were primed (usually flight times). If I wanted to fly another time I just called my mechanic up and had him go plug the plane in directly.

Now I have one of those GSM Auto based units (similar to what Phillipe sells here, but I ordered before he showed up on the scene and had to build all the interface parts myself) that I can send a text message to to crank it up.
 
paflyer said:
With the latest, early bout of Global Warming hitting most of the country, it's perhaps time for the annual resurrection of this thread.

My PA28 is hangared but unheated. It is a @*$&!!! to start when it's cold (like below 45deg.)

So here's what I'm thinking for a cheapskate heater: get a couple electric heating pads (like for your bad back) put one on each side of the engine (the upper cowling is hinged/split), put in the cowl plugs and wrap the cowling with a moving blanket. Maybe cover the prop as well since it's a big heat sink. Put the heaters on a "travel" timer set to come on at midnight and run until 9AM (to be determined experimentally). The engine should be toasty, or at least at room temperature, in the morning, right?

Any holes in this plan?
Click to expand...

You want to put them under the cylinders and oil pan. Heat rises.
 
txflyer said:
The colder it gets, the more I prime and mine starts o.k. but I'm not in real cold country.

It's a dilemma especially when you don't have block heat.

I don't like leaving anything on unattended because of the related risks, but if I had a block heater and it's sub freezing, I'd use it or at least try to pre-heat with it before a trip. There's gotta be a app for that .. :rolleyes2:
Click to expand...
there are a number of GSM switches you can get that can be turned on/off by cell phone.
 
murphey said:
there are a number of GSM switches you can get that can be turned on/off by cell phone.
Click to expand...



Affirmative.

I may end up with one some day, but where I live, I can get away with a quick pre-heat or no heat usually.
 
Note if you get a GSM switch and you have a metal hangar you will need to have an external antenna most likely. That was a DUH moment when I installed mine. It worked great with the hangar door open but nothing when it shut. Fortunately, I had a cell phone antenna lying around from another project (attempt to use it for security cameras) I connected it up to the GSM auto and stuffed it out a gap between the top of the door frame and the roofing material.
 
flyingcheesehead said:
Doubt it. Those pads don't get nearly as hot as, for example, the cylinder bands on a Reiff preheater. You're likely to end up with the top half of the engine/cylinders warmer than the bottom. Your oil will still be very cold and thick and not get to where it needs to be very fast (which is one of the primary reasons for needing to heat in the winter), and your cylinders will be heated unevenly and have increased wear.

It might be easier to start - or it might not - But that would be about the only "advantage" of heating it this way.

Don't be a cheapskate - The Reiff Standard System (which includes bands around each cylinder as well as an oil pan heater) is a whopping $435, with 2-4 hours of labor for installation. That's a tiny fraction of the cost of an engine overhaul.

The "cheap" methods for warming your engine in the winter are a false economy. There's no substitute for doing it right.

http://reiffpreheat.com/
Click to expand...

The Reiff system also creates uneven temps, at least in the short term. I don't think a few tens of degrees of delta is going to create excess wear.
Also, with labor rates around here the full install price is more like $750.

I'm only interested in creating an environment for the engine compartment that is maybe 10-20 deg warmer than ambient over the space of a few hours, which should take the chill out of the entire engine block (eventually). So if it's at freezing outside, under a well insulated cowl it's perhaps 50, which is where there's generally no issue with starting. It's not as efficient as block heaters, but it's inexpensive.

I'll have to get a non-contact thermometer and test the theory. Biggest question is how long it takes to be effective.
 
I think a backache heat pad is going to leave you cold and disappointed. They're designed for direct contact. They don't produce ambient heat to do anything meaningful. If you're in a hangar, you might as well just get a 1500 watt space heater (type with a fan) and a piece of dryer duct. Let it blow up into the cowl the night before and it will probably be very effective for what you're trying to accomplish.
 
Pedals2Paddles said:
I think a backache heat pad is going to leave you cold and disappointed. They're designed for direct contact. They don't produce ambient heat to do anything meaningful. If you're in a hangar, you might as well just get a 1500 watt space heater (type with a fan) and a piece of dryer duct. Let it blow up into the cowl the night before and it will probably be very effective for what you're trying to accomplish.
Click to expand...

Fastest, easiest and cheapest way is to buy a oil pan heater from these guys,, Stick it on the sump, plug it in and an hour or so later the motor is nice and warm......


http://www.archeat.com/
 
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Henning said:
You want to put them under the cylinders and oil pan. Heat rises.
Click to expand...

Yes, but conduction is a more efficient method of heat transfer than convection, so you'd also want them bungeed to the bottom of the engine or something. And before long, you're running into a situation where it's more of a pain than it's worth and you risk dropping something down into the bottom of the cowl.

Again - No substitute for the real thing if you live in a climate where it's a necessity for any length of the winter. I would only try these makeshift things if I lived in TX, FL, AZ, CA etc where it doesn't routinely get into preheat territory in the winter.
 
N801BH said:
Fastest, easiest and cheapest way is to buy a oil pan heater from these guys,, Stick it on the sump, plug it in and an hour or so later the motor is nice and warm......


http://www.archeat.com/
Click to expand...
How is a stick on oil sump heater going to heat the entire engine and contents in an hour???



<< Sent from my mobile device at 0agl >>
 
Pedals2Paddles said:
How is a stick on oil sump heater going to heat the entire engine and contents in an hour???



<< Sent from my mobile device at 0agl >>
Click to expand...


Heat rises... Conduction, and it helps ALOT if you throw a thick blanket /,comforter over the cowling..... Mine stays plugged in 9 months out of the year.. And I only use the 175 watt unit... If you get the 300+ watt one, that sucker puts out some serious heat...
 
flyingcheesehead said:
Yes, but conduction is a more efficient method of heat transfer than convection, so you'd also want them bungeed to the bottom of the engine or something. And before long, you're running into a situation where it's more of a pain than it's worth and you risk dropping something down into the bottom of the cowl.

Again - No substitute for the real thing if you live in a climate where it's a necessity for any length of the winter. I would only try these makeshift things if I lived in TX, FL, AZ, CA etc where it doesn't routinely get into preheat territory in the winter.
Click to expand...

Sure, you stuff them between the intake tubes and cylinder and it has a lot conduction, way more to the oil pan.
 
Pedals2Paddles said:
How is a stick on oil sump heater going to heat the entire engine and contents in an hour???



<< Sent from my mobile device at 0agl >>
Click to expand...

With 750Watts of electricity, the oil is what you want warm, cylinder heads warm up quickly with just few power strokes. The oil is also a big heat sink and if you put an insulating wrap on the cowl the oil sump heaters work really well even in really cold conditions.
 
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