Winter preheat using a generator

Sometimes, yes, but I keep one at home and another at the cabin so it depends on my destination. I can’t wear out the two Yamahas that I have but the newer inverter models are lighter and smaller, and use less fuel. I also have a Honda 2000w inverter type but the Yamaha is usually what I use for the airplane because it fits on the floor in front of the truck’s passenger seat so it’s easier to stow when I go.

Honda and Yamaha current model 1000w generators weigh less that 30#. Very handy.

There are guys in Alaska who keep their small gennies in aft baggage and make exhaust extensions so they can run the gennies inside the plane. They keep them there all winter. Necessity is the mother of invention. :)
 
My two cents...you should be able to bag the exhaust to keep the nasty stuff from 2 cycle out of the engine, however, you may be getting a lot of CO2 into the cockpit and it should be vented before you fly. I've hear of lots of folks in the north doing the oil heating off board. If you are changing it anyway, you'll want warmer oil so it will at least flow into the engine. Finally, think about getting a battery warmer to plug into the generator as well.
 
Nobody removes their oil. The idea that 6-7 quarts of warm oil will help a cold soaked 300# engine is silly. Think about it. What it would do is make water vapor. Not a good plan for cold starting. In the old days they didn’t have better options. We do.

Most northerners lost the flooded batteries decades ago. AGM batteries work great in the cold without preheat. I never heated a battery before AGM, either. A preheated engine will make spinning it easy for any healthy battery. With proper preheat you can hand prop in one or two blade pulls. That’s what you want for your starter, too.
 
I can't imagine a portable generator makes enough heat to worry about trying to do something with the exhaust.

How long are you going to run this generator? Electric pad heaters take a good long time (hours) to bring the engine up to temperature.
 
I applaud your desire to fly. I love flying and take a lot of opportunity to but I don’t know if I’d be committed to but 3+ hours into warming up a plane for winter flying but you gotta do what you gotta do!!!
 
View attachment 69306 A Little Buddy is the most useful heater you occasional users will ever find. 900w heat with a circulation fan. No tip switch. All metal construction. Overtemp shutoff built in. Mine rode attached to my engine mount for several years before I removed it and it still works perfectly. It takes a long time to heat oil this way so if you want faster heat-up add a 75w silicone heat pad to the sump and you’ll have a very useful system. And yes, I use a 1000w generator. Always have. Still do.

:yeahthat:

For years this is what I used. A quilted cowl blanket and that little heater would make the engine in my Cherokee toasty in 3 or 4 hours depending on ambient temp. If it was cold enough to require longer than that, it was cold enough to stay home in front of the fire with a hot toddy.
 
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I applaud your desire to fly. I love flying and take a lot of opportunity to but I don’t know if I’d be committed to but 3+ hours into warming up a plane for winter flying but you gotta do what you gotta do!!!
3 hours is what I shoot for. At the airport by 6am, hook up generator and start the preheat. Uncover the wings, fuselage and tail. Shovel snow if needed. Put a small heater inside cabin and get that warming. Go home warm up and eat breakfast. All for a 1 to 2 hour flight....:rolleyes:
 
I applaud your desire to fly. I love flying and take a lot of opportunity to but I don’t know if I’d be committed to but 3+ hours into warming up a plane for winter flying but you gotta do what you gotta do!!!
I'm still getting better at this but right now for a flight at 0F deg I get to the airport 1hr early. The night before I remote start the Tannis. Man, I should have done that last year. Anyway, I plug in a small ceramic tipswitch heater in cabin immedietly. I then preflight and put in the gadgets. That leaves about 30min which I use to blade away snow, hit the bathroom, get rid of the heavy jacket and boots, etc.

On Saturday it was +15F and easily +60F inside the plane when we hoped in. That full hour of cabin heat really helps! The Skylane heater at cruise doesn't hurt either :)
 
1) Exhaust is bad because it's corrosive. Covered by many above. I kind of like the idea of running the tube in and out of the cowl and capturing some of the heat that way though.
2) If you want to be efficient, you'll need to at least tie another blanket around the outside of the heating blanket, otherwise most of the heat from the heating blanket will be lost.
3) Heating the oil is not going to help warm up the engine parts, which is also important. Think about this in terms of thermal mass... <10 pounds of oil, even at 200 degrees, is not going to significantly change the temperature of 250 pounds of engine.
4) Unless you're in an area where your overnight lows don't go below 20ºF, you're going to need to heat the engine for a long time to really get it ready to go with the setup you describe. Personally, I would go for a Reiff Turbo XP system that gives you 100 watts per cylinder plus 200 on the sump. That's 600 watts, all in contact with the engine, and will be able to heat it sufficiently in just a couple of hours instead of overnight (and overnight your generator would probably run out of fuel anyway).

This article is a must-read for anyone who owns an aircraft and flies it in cold weather: https://www.avweb.com/news/maint/182846-1.html

Pretty sure that’s not true, as it isn’t used in flight. It’s just a sticker. When you’re flying it’s just well-secured cargo.

Doesn't matter whether it's used in flight. What matters is whether it's attached to the airplane.

Nobody removes their oil. The idea that 6-7 quarts of warm oil will help a cold soaked 300# engine is silly. Think about it. What it would do is make water vapor. Not a good plan for cold starting. In the old days they didn’t have better options. We do.

Oh, they do. I've seen it happen. I agree that it's largely worthless in terms of heating the engine, though it at least gets oil moving to all the parts quickly.
 
[QUOTE="Sinistar, post: 2634776, member: 29060
On Saturday it was +15F and easily +60F inside the plane when we hoped in. That full hour of cabin heat really helps! The Skylane heater at cruise doesn't hurt either :)[/QUOTE]
The cabin heat in our Skylane is all or nothing!! We try to just crack it open and we have to turn it off in about 15-20 min. I tend to cycle it now on and off. This winter I plan to fly more so I am going to work on getting that part right.
 
[QUOTE="Sinistar, post: 2634776, member: 29060
On Saturday it was +15F and easily +60F inside the plane when we hoped in. That full hour of cabin heat really helps! The Skylane heater at cruise doesn't hurt either :)
The cabin heat in our Skylane is all or nothing!! We try to just crack it open and we have to turn it off in about 15-20 min. I tend to cycle it now on and off. This winter I plan to fly more so I am going to work on getting that part right.
My heat in my PA28 is the same way: really hot, but all or nothing. When its mild, I just use defrost. As it gets colder, I cycle heat while running defrost. Only when its > -20F do I leave heat on 100%.
 
So we had used a torpedo heater just once on my wife's Aeronca Chief. We needed to move it during the winter and it was really cold. It was in a unheated hangar so I put a large tarp over the front of the plane and put the torpedo heater in front but several feet back and then blasted the heat under the tarp. So we didn't directly blow the heat into the cowl. Definitely didn't want that hot air going right against the metal and paint. About every 10 minutes I would feel the motor to see when it finally felt warm. I think it took about 90 minutes this way, maybe even a bit more. The oil seemed to heat up nice and it hand propped on the first try at about -5F.

I probably wasn't clear enough: When I say use a torpedo heater I guess I meant to heat a small volume around the engine, not blast it straight into the cowl. But once again, this was in a hangar so the tarp wasn't blowing all over the place. The OP surely doesn't want to mess with all this as it would require hassles to setup the tarp plus need a torpedo heater and fuel source along with the generator.
 
The cabin heat in our Skylane is all or nothing!! We try to just crack it open and we have to turn it off in about 15-20 min. I tend to cycle it now on and off. This winter I plan to fly more so I am going to work on getting that part right.
I have the heater all the way out and defroster all the way up at startup. After about 15min at cruise it starts making too much heat. Eventually (say 1hr cruise) I find I have the heater knob pulled out about 5% and the defrost knob opened just one or two clicks (about 15% max). So yeah, it makes plenty of heat.
 
A couple of these under the cowl and a moving blanket over it will do a lot more than the exhaust will.

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Yeah, but the entire point of investigating the exhaust was that it is “free”. The more load you put on the generator, the more waste heat is generates in the exhaust for “free”. Find a way to use it and you have faster and cheaper heat using a smaller generator.

I’ll work on it this winter to come up with some cheap easy way to use the heat and not corrode the engine with direct exhaust exposure. Best thing I can think of is a hair dryer running on 600 watts blowing into a 2” AL flex hose that runs inside of a 3” AL flex hose exhausting the generator. Like a counter flow heat exchanger where the little hose enters the side of the larger hose and runs inside, then exits back out the side. Plus the 100 watt heated blanket cowl cover and a 75 watt stick on oil pan heater maxes out the 800-900 watt generator and uses all the available energy with low cost.

I just made a full wing cover out of some scrap fabric I had lying around. Not bad for a 2 hour prototype. Needs some better fitting, but it is cold outside and I did not want to waste too time and money on the first prototype. I have an industrial sewing machine setup in my shop with a 36’x36’ floor so it was an easy quick project to try to save the $300 for a commercial cover.
 
I would opt to drain the oil into a 5 gallon metal can after each flight and refill the sump with warmed oil.

That is the way they used to do it in the olden days. Drain the oil, take it inside and put it next to the wood stove. Nice and warm the next morning. Pour it in and go. Bonus points were awarded if the pilot did not burn the cabin down.

Some of the hardier bush pilots would put a long canvas cover over the cowling letting it go to the ground, then build a fire under the plane. Pilots were considered good if they didn't set the canvas on fire and still got the plane started.
 
For pre-heat on the ramp I think an insulated cowl cover would be a worthwhile investment. If it's really cold and the wind is blowing, a 300w oil pan heater may not be able to put heat into the engine faster than the wind blows it back out without some insulation. I have learned this from experience. Good luck.
 
A couple of these under the cowl and a moving blanket over it will do a lot more than the exhaust will.

How do you know? Don't you fly a Mooney? There's no way in hell two 10" lights fit under your cowl. :D
 
Yeah, but the entire point of investigating the exhaust was that it is “free”. The more load you put on the generator, the more waste heat is generates in the exhaust for “free”. Find a way to use it and you have faster and cheaper heat using a smaller generator.

I’ll work on it this winter to come up with some cheap easy way to use the heat and not corrode the engine with direct exhaust exposure. Best thing I can think of is a hair dryer running on 600 watts blowing into a 2” AL flex hose that runs inside of a 3” AL flex hose exhausting the generator. Like a counter flow heat exchanger where the little hose enters the side of the larger hose and runs inside, then exits back out the side. Plus the 100 watt heated blanket cowl cover and a 75 watt stick on oil pan heater maxes out the 800-900 watt generator and uses all the available energy with low cost.

I just made a full wing cover out of some scrap fabric I had lying around. Not bad for a 2 hour prototype. Needs some better fitting, but it is cold outside and I did not want to waste too time and money on the first prototype. I have an industrial sewing machine setup in my shop with a 36’x36’ floor so it was an easy quick project to try to save the $300 for a commercial cover.
You want free? Wait for summer.

Two 100 watt incandescent bulbs will probably be more effective than your blanket and stick on heater. You’re not going to get any measurable amount of heat out of an exchanger from exhaust from an engine that small unless you run it for days.
 
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How do you know? Don't you fly a Mooney? There's no way in hell two 10" lights fit under your cowl. :D
I also live in Florida.
Pop off the cheek panels and you could fit 4 of them under my cowl. :D
 
I have had the same experience with the small Yamaha generators as well, takes a lot of pulls when it's cold, and it will usually auto shut off once or twice till the oil warms up. My wife made a insulated blanket to put over it, so run it, if it stops, throw the blanket on for a few minutes, start it again, always worked out. I did try to take it in with me when ever possible, but didn't always work out.
As a recommendation, I suggest familiarizing with this article, a great source of generators review!
 
I must be a total dip****. I just had my airplane towed into a heated hangar when it got that cold. Didn't have to do it more than a few times during most winters.
 
A related question: does anyone know if there is such a thing as a remote start for a generator? I have electrical now and use a switchbox and remotely turn on the electrical to get the Reiff Turbo XP going. Awesome setup. But the airport is talking about tearing down our hangars to support expansion and I can see the day when I lose my electrical. In that case, does anyone know of a generator with a remote start, or is there a way to hook up a switchbox to start a generator remotely?
 
I must be a total dip****. I just had my airplane towed into a heated hangar when it got that cold. Didn't have to do it more than a few times during most winters.

In a couple weeks every first start will need preheat here. I've flown 4 times in the past two weeks, each one required preheat, fortunately the plane is equipped with block heaters and remote switches, so the place I rent from has them nice and toasty before we go. KBED.
 
I have started my IO-520 engine many times down to 10 degrees F without pre-heat and absolutely no engine damage (since I do my own major overhauls I would see it). However, I am careful to start the first time the engine fires to avoid frosting the plugs. I use multi-viscosity oil and will connect my car battery as a boost when it is really cold.
 
Your goal is to heat the whole engine. I say a pad heater and inulated cowl cover. If you sewed wing covers, make a cowl cover- I did. Its insulated as hell, and even with only a sump heater top area of my cowl is 80 plus degrees even when cold. Those little generators will run 6 hours or so on a tank, it should be plenty toasty with a 300w sump heater on it. I will go lazer temp my cylinders soon to get a reading on those, I think the Reiff and Tannis are great but with an insulated cowl cover even a sump pad will get the cylinders warm...

Yes if you are going to use exhaust engineer something based off how our cabin heat works basically...
 
I will say this, some of you guys sure want to go flying really bad to be out in the wind doing all the procedures suggested. If I could not hangar my plane, I would not own one in cold climates.
 
There are different levels of cold, North GA cold, or North MN cold.

If just a few times a year, one can improvise as needed. If one lives further north(me) you almost need a dedicated heating element installed. That’s usually a plug-in type.

If a plug-in, away from home or power, extension cords or a small generator does the trick.
 
I will say this, some of you guys sure want to go flying really bad to be out in the wind doing all the procedures suggested. If I could not hangar my plane, I would not own one in cold climates.

The whole flying thing is a series of hurdles. Money, time, money, time, frustration, money, bureaucracy, time... Preheating outdoors is just another hurdle to clear.
 
Not sure if someone mentioned, but a decent Walmart sleeping bag makes a good cover to hold in heat
 
I must be a total dip****. I just had my airplane towed into a heated hangar when it got that cold. Didn't have to do it more than a few times during most winters.

Whether or not you're a ds depends on how long you leave the plane in the heated hangar before you start it, and just how heated said hangar is. Many "heated" hangars are only heated to 35-40ºF, which IMO is pointless. If it's 40 and your plane is parked there all the time, maybe... But if it's 40 and your plane is in there for an hour, still pointless.
 
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