Cold Weather, Remember how to Start Engine

A guy showed me a trick for cold starting the C172SP IO-360: after running the fuel pump (mixture rich), wait 60-120 seconds for the fuel to vaporize in the cylinder, then attempt starting (mixture cutoff until she fires, usually 2-3 blades). Worked well for me when I was working as a CFI.
 
How big is your fire extinguisher? :mad3:

To be serious, no I haven’t. That would be a lot of ether that’s in the long and wide intake tube leading to the carb box. A backfire at this time would be a fuel air “boom”. The idea gives me great pause. Interested in hearing others.
 
AV8R_87 said:
I wonder what their reasoning was. That air is usually less than 120F, and it uniformly warms up the engine. I don't see any issues with doing that to an engine for an hour or two in cold weather, warming everything up.
If anything, I wonder if their concern is not warming the engine enough, leading to uneven temperatures. I recall some people were against oil pan heaters because it did nothing for the cylinders.
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I have a vague recollection of someone explaining to me that with continentals the moisture evaporated out of the oil would condense further up in the engine and cause corrosion problems. Hopefully posting this will get someone to confirm or deny.
 
AV8R_87 said:
I wonder what their reasoning was. That air is usually less than 120F, and it uniformly warms up the engine. I don't see any issues with doing that to an engine for an hour or two in cold weather, warming everything up.
If anything, I wonder if their concern is not warming the engine enough, leading to uneven temperatures. I recall some people were against oil pan heaters because it did nothing for the cylinders.
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As I recall, it was a concern about uneven heating.
 
Gilbert Buettner said:
When I owned a V-tail Bonanza, the engine operating instructions specifically advised against this way of pre-heating. I used an oil pan pad heater and a big quilt or moving blanket over the cowl. Always the night before flying in northern Minnesota, Wisconsin and lower Michigan. I often flew when OAT was below zero F.
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AV8R_87 said:
I wonder what their reasoning was. That air is usually less than 120F, and it uniformly warms up the engine. I don't see any issues with doing that to an engine for an hour or two in cold weather, warming everything up.
If anything, I wonder if their concern is not warming the engine enough, leading to uneven temperatures. I recall some people were against oil pan heaters because it did nothing for the cylinders.
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On my Mooney I have 2 Revlon hair dryiers. Low is about 800 watts. I put one in each cowl flap and a blanket over the cowl to heat both sides evenly. I preheat if below 30°F. I also own a battery operated propane forced air heater. I thought I could use it if away from home, but it is not as reliable.
 
If you are cold starting a carburerated engine with a working fuel priming pump this method will start it every time. Set carb open about 1/4 throttle, or just crack open about twice as far as you normally would on a warmer day. Pull the primer out and be ready to pump. Begin cranking and after the first blade passes the windscreen begin pumping vigorously until it starts, then stop pumping. Be ready to pump again in 2-3 seconds if the engine stalls. Adjust throttle and pump again as needed to keep engine running at low speed until pumping is no longer needed. Lock down the primer and let the engine warm up at low speed.

This works because you are moving the AF ratio from a too lean to fire condition to a rich enough to fire condition. If it is cold outside and the engine is cold it will likely go lean and stall again 2 seconds or so after starting. Pump again as it spins down just enough to keep it running. As the heat builds the gas will evaporate better and engine will run OK on its own. This method worked every time on my old Cherokee O-320 Lycoming.
 
it’s unlikely the two hair dryers can adequately warm the oil in an hour or two in sub 10° temperatures, which is what Lycoming uses as their preheat threshold.
 
WDD said:
Us tie down, hangar challenged folks without electricity just have to make do with propane.
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Actually someone here pointed out the jackery line of portable batteries…just plug in your tanis to the jackery and 30 minutes later you can go!

Of course that works once unless you have a solar panel or a regular outlet to recharge from
 
Pinecone said:
And they were against LOP operations. :D
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I don't agree that Lycoming excludes LOP operations. Service instruction 1094D states:
"For a given power setting, best economy mixture provides the most miles per gallon. Slowly lean the mixture until engine operation becomes rough or until engine power rapidly diminishes as noted by an undesirable decrease in airspeed. When either condition occurs, enrich the mixture sufficiently to
obtain an evenly firing engine or to regain most of the lost airspeed or engine RPM. Some engine power and airspeed must be sacrificed to gain a best economy mixture setting."

That sounds like LOP operations to me.
 
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