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preheat with a heat gun?


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23 minutes ago, PT20J said:

Oh man, this is making me travel back in time to chemistry class. I hated balancing equations, but his one is pretty simple. Avgas is a complex brew of hydrocarbons and other chemicals, but to use the octane example, complete combustion would combine the octane with just enough oxygen to result in the production of only carbon dioxide and water.

2C8H18 + aO2 =bCO2 + cH2O

Balancing carbon: b=16

Balancing hydrogen: c=18

Balancing oxygen: 2a = 2b + c, or a =25

I'll let someone else figure out the weights :)

Skip

Thanks, you did the hard part! Once upon a time, I could write and balance the combustion equation for any hydrocarbon fuel, estimate the efficiency of its burn and make a reasonable approximation of the other combustion byproducts and the temperature. 

But atomic weights are easy!

  • Carbon = 12
  • Hydrogen = 1, but mostly occurs as H2 = 2 except in compounds (like fuel)
  • Oxygen = 16, but occurs as O2 = 32 (except in unwanted byproducts like CO and NO)

After a great supper of Italian-styke pizza with tomatoes and olive oil imported from Italy, and some nice dark beer, I don't feel like doing the math. But here are the numbers for whoever wants to give it a try . . . . .

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Stoichiometry and MS... perfect together..!

Proof that you can get smarter... just by reading the internet...  :)

Lots of fuel being burned...

Which is often easy to keep track of using a FF instrument.... or knowing how many gallons You purchased... then used...

What is really hard to measure... air flow... we don’t usually measure the airflow directly in our planes... MP gives us a close hint...

The engine manufacturers probably have a chart of air flow (cfm) vs. MP for our engines...

Then a quick study of our nature science book to know how much O2 is in that air...

That’s a lot of air being drawn in... and plenty of O2 being attached to H2s... making a lot H20...

+1 for not stuffing exhaust by-products into your cowl... my cars burn pretty cleanly, but... the exhaust pipes are not the cleanest instruments...

PP thoughts only, not a bio chemist...

Best regards,

-a-

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On 11/5/2020 at 11:33 AM, Dale Logsdon said:

I know a guy who uses a cheep hair drier he bought from Walmart and thinks its the best thing ever.

I take it he lives in Oklahoma, where "cold" means there was frost on the ground this morning. Where I live, DIY solutions that do not involve industrial strength heating, such as a large salamander in an enclosed space, are not worth anything. The FBO keeps a propane powered salamander and a heavy cowling blanket which they occasionally use to get people started in the winter who do not have the proper equipment. It would be fun to watch a rookie out on the ramp trying to heat his engine up with a hair dryer or heat gun at 20 below though, we would all watch from the windows and cheer him on.

I had a heating system installed over a decade ago, now I don't even remember which one it is, Reiff or Tanis, but I do recall that one of them does not work on engines that have complete engine monitoring systems such as the JPI 930 in my aircraft. Interference with the probes for the engine monitor. It works really well and has been very durable, if you wish, you can even just leave the aircraft plugged in all the time, with the oil cap cracked so the moisture can leave.

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PS even with an engine heater you can’t just plug it in 10 minutes before you start up. I try to give it four hours and overnight is better.

It is possible to start the engine at +20 dF, I have done it on a few occasions when the line guy at the FBO failed to plug the hearter in on my plane when he was supposed to, but I really don’t like to. It is hard on the engine, and very hard on the battery. Best to get the oil temp to at least 40 dF and 50’s or 60’s is better. 

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Sixty minutes with my Tanis is all it takes. Longer works well, but 60 is the minimum. It can be hard waiting away from home, after being moved near a plug.

The cell switch is also very nice! I loved mine, but it was a 2G device bought here. Don't really need it now, unless I travel north during their bad season.

And for the naysayers:  we have four seasons here in Alabama! Just this week, we had winter every morning when I got up at 0515; by mid-morning, it was spring; followed by summer at lunch, sunny, blue and warm; and into fall by the time I got away from work (1630-1700). 

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On 11/6/2020 at 3:32 AM, M20Doc said:

We heat our daughter’s Cessna 150 with a 60 watt light bulb in a trouble light and a pair of old sleeping bags on the cowl. We slip the light in the bottom of the cowl opening.

Yes! This with two lamps hooked up to a temperature activated switch that we used to use in the cows' watering tank in the winter time!

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