Engine preheater

Harley Kleemann

Now that I finally am moving from a common hangar to my own T-hangar, I am looking at a Tanis engine heater for my Arrow. Seems to be a good system. Anyone have experience with this one?

griff390

Harley;

I live in the Midwest where we get every kind of weather from -20F to +100F. My plane lives in an unheated T-Hangar. When the weather begins to change, I plug my Tannis heater in and leave it plugged in all winter. There's a debate that rages along the lines of "leave it plugged in all the time" vs. "plug it in 2 hours before using the plane". Tannis says yes, leave it plugged in, but others have posted that Continental says no.

I won't engage in the war, but I can tell you that since I started plugging it in all winter, my engine oil analysis has improved substantially. I put in the cowl plugs and have old sleeping bags that I wrap around the cowling to help keep the heat in. The residual heat from the heater keeps the dew point inside the engine high enough that condensation has a difficult time forming. The oil analysis shows that metal content due to ferrous metals (which are most likely to rust) has plummeted. Engine dryers help also, but the best thing is to fly it often. Unfortunately, that's not always an option in our winters.

My system has the cylinder heaters as well as the oil pan heater. It works fantastic, and the oil is always pre-warmed when I'm ready to fly. During winter months, I pre-flight the plane in the hangar and leave it plugged in until I'm ready to push out.

griff390

PS - I have also begun opening the oil cap immediately after flying to vent out any moisture/steam built up during flight. Some people leave the cap open, I close it after 20 - 30 min. I don't want any foreign objects falling into the crankcase while I'm not around.

Harley Kleemann

Jim, I have the same type of weather you do...-40 in January to 110 in the summer. I remember one January here in Bismarck not too many years ago...the temp at 8:00 A:M was -46. That was not wind chill, that was the actual temp. We took a cup of coffee outside our office and slung the coffee in the air. It turned to vapor, and not a drop hit the ground!

North Dakota...makes you tough or kills you!

griff390

Harley; lol, then I don't have to tell you about the crazy Midwest temp swings, you're living it!

Back to the Tannis, if you don't have one, I highly recommend it, especially knowing your weather, and the fact that your plane will be in an unheated hangar.

I agree, whatever doesn't kill you makes you tougher. And we have really good scotch to help recover from the tough bouts.

Scott Sherer

I've owned just about every engine preheater that Aircraft Spruce sells over the years and they all do the job. My Turbo Arrow III came with a Tanis system and it works very well, too. I also have a battery heater and charger that I plug in during the last hour with the Tanis. And I also let the steam vent out of the engine right after shutdown, too. I open the oil cover and let it vent while I'm putting the plane away. By the time I get it in the hangar it's done venting and I put the cover back on.

Harley Kleemann

Called and spoke with the nice folks at Tanis. The gentleman I spoke with told me that the heater can be left plugged in and heating all the time without using a remote switch, timer, etc. He said that cowl plugs and an old blanket over the cowl will keep the engine nice and warm without condensation forming in the engine.

griff390

Harley;
That's been my experience to a tee, and my oil analysis confirms it.

Harley Kleemann

I'm heading out to the airport this morning to meet with the maintenance supervisor at Bismarck Aero Center and get the ball rolling. Tanis said that while they technically COULD sell the equipment to me, they prefer to support their dealers and have me buy locally, so that's what I'll do.

alschm

Slightly different topic, but still pertaining to cold wx. We have a Dakota and keep it in a heated hangar at our FBO in Great Falls, MT. What do you all use as guidelines for go/no go on outside temps? Our CFI says he doesn't like/allow anyone to run his 140 and Archer trainers at < 15 F. Those are also kept in the same heated hangars.

Seneca38173

Hi Art -

What's your CFI's rationale for the 15F cutoff? We mostly fly in the high teens or low 20s, where the outside temp is routinely -20 to -40F. So long as the flight controls are lubricated with the right stuff (aeroshell 5 or 7), the cabin's warm, and the engines are preheated, what's the concern?

Bob T.

griff390

Alschm;
IIRC, our flight school had similar guidelines.
Pre-heat required at 32F or below. Note: Continental says 20F, and preheat for at least 30 min, while Lycoming says 10F and apply heat at 5 - 10 min intervals, until the entire engine is warm.
No pattern work at 15F or below.
No flights at -5F or below, x-country not allowed.

The numbers above were what I recall from flight school, and not necessarily from Continental or Lycoming except where noted. Flight schools will probably be a little more conservative with their restrictions, as students tend to be tougher on equipment than owners. Shock cooling can be expensive. Ask me how I know, even though I didn't do it.

Extreme cold (-20F and below), brings a whole different set of problems. For instance, many engine oils have pour temps in the -29F range. That means a cup of fresh engine oil at or below that temp will not pour. You could turn it upside down and the oil will stay in the cup. Used oil is worse. Pre-heat is mandatory.

I don't need to fly in those conditions, but to pilots in colder climates, it's no problem. They are prepared and know how to handle it.

Here's a couple links to check out.

https://www.avweb.com/ownership/whats-cold-for-a-piston-aircraft-engine/

https://www.lycoming.com/content/operating-cold-weather

alschm

Thanks for the feedback. I don’t recall the exact reasons our CFI didn’t want his flown at cold temps, other than he has a great deal of experience and has probably arrived at that cutoff based on MX experience.

I’ll look over these links and form some personal and airplane minimums over time as we get more accustomed to our plane. Unfortunately, some of the nicer days up here in the frozen tundra are on clear, but very cold winter days. It’s the price we pay to keep the riff raff out of here (present company excluded) 😜

Harley Kleemann

Personally, I prefer to fly when it's cooler. Engine makes great power, I can get up to 6500' and still see 25" of manifold pressure like this past Monday when I did my BFR.

griff390

Harley just nailed it. Cold weather flying can be a lot of fun. Makes you feel like your plane just gained 40 HP.

arrow76r

I pay the electricity bill for my hangar condo units so see who pays your bills then decide if a timer is warranted. We STRONGLY recommend a timer so that the electricity bill (which all 10 units share equally) stays low!!!

Scott Sherer

I have no lower temp limit for flying on my plane. However, I have a lower limit and it has to do with windchill. Ten to fifteen degrees is my lower limit and it jumps to 15 to 20 when it's breezy out. And in Wisconsin it's almost always breezy in the winter.