Question engine preheating

Hi Doug,
I spoke the tech guy at Tanis Air and he said that the condensation occurs when the oil is heated but the case is not. As the oil heats up moisture evaporates and condenses on the cold case. So repeated short term heating then not operating the engine is conducive to moisture condensing on the case.
If there's a heating pad on the case this effect is lessened.
He also said you can leave the heater on continuously to prevent moisture condensation inside the engine.

Thanks for the reply. What are your techniques for preventing water condensation in the engine case?

Alyssa;
As all the cool kids say,
"You've got it goin on!"
I love the idea of the cabin heater- esp important if you still have spinning gyro instruments in your panel. If not, it's still a great idea just for the comfort you'll feel when you first start up.
I also am a big fan of sheep skin seat covers. Warm in the winter and cool in the summer.
If you're going to get them, make sure you get good ones--they're sorta spendy but we are worth it.
Steve

STEVE ELLS wrote: Hi Doug,
The prevailing attitude is to turn on the engine heater about 4 to 8 hours prior to initial engine start.
HangarBot sells a switch that can be operated by a cell phone signal. If there's electrical power in your hangar, cell reception at your hangar and you need to pre-heat that seems like a pretty slick set up.

This is pretty much the process I follow. I have a Tanis heater and if I know the temps will be below 45 degrees I will fire up the heater 6-8 hours before my planned flight. I have a similar switch from Switcheon (with Tanis branding on it) that has two outlets that can be separately controlled via their phone app. The box itself uses a 4G mobile connection so you don't need wifi. I generally try to be sure I'm actually going to fly before I turn it on. There is some discussion of cycling it on and off without starting the engine causing corrosion. From what I've seen discussed this was more of a concern on Continental engines but I've seen just as many claim it's not an issue at all.

In addition, I recently bought a small space heater with a digital thermostat and tip-over protection to use as a cabin heater (at the suggestion of my CFI/A&P-IA). This is mostly to keep the gauges and avionics at a reasonable temp. I leave that one turned on all the times since the digital thermostat controls when it runs and it only has a small area to heat. I just set it to the lowest temp which is 60F so it doesn't run too often and I can still switch it off remotely with the second outlet of the switcheon.

Hi Doug,
The prevailing attitude is to turn on the engine heater about 4 to 8 hours prior to initial engine start.
HangarBot sells a switch that can be operated by a cell phone signal. If there's electrical power in your hangar, cell reception at your hangar and you need to pre-heat that seems like a pretty slick set up.
The low budget solution is to go to the local thrift store and pick up an inexpensive sleeping bag.
Lay the bag over the cowling, then put a trouble light with a 60 watt bulb up under the lower cowling the night before.
Although I live in a climate where it's almost never necessary to pre heat, I would definitely pre heat my Lycoming when it get below freezing; it seems that 10 F is pretty cold for a non heated start.
Hopefully others will weigh in on their practices.
Steve

It is again that time of the year when those of us in cold climates become concerned about engine preheating. I found a Lycoming Service Instruction, No. 1505, addresses the subject but only using high volume hot air. I am of the opinion most use some type of electrical heater. Also, Lycoming is recommending preheating with temperatures 10F or colder.

There is an article from Tanis that I have found to be contradictory in some aspects. I prefer not to analyze the article now but pose the question: is it a good practice to connect the electric preheater and leave it plugged in all winter? Or, is it better to plug in the preheater some reasonable time prior to flight, fly, and leave the heater unplugged once back in the hangar until you are going to fly next?

Of course, the ultimate goal is prevent moisture from forming inside the engine.