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Cold Starts without pre-heat

H

Hornet2008

Well Known Member
Hi All. We are experiencing winter in Australia while the lucky people in the north have warmer climes. Gets sub zero here, we measure temperature in Celsius. Reading Mike Busch's book on Engines he states you should never start a Lycoming below 32 degrees F. I have my Dynon EMS set up in degrees F and don't start unless temp is at least 40 degrees F. What I am finding is the oil pressure is agonisingly slow to come up. Takes about 30 sec to 40psi. Newish engine, 41 hours, Shell straight 100 oil.
Is this going to harm the engine?
 
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Depends.... ;-) How long since the last run? I feel that's more important to preventing engine wear, but it sure wouldn't hurt to have it a little warmer, even with a simple light bulb and some cowl wraps.

-Marc

Hornet2008 said:
Hi All. We are experiencing winter in Australia while the lucky people in the north have warmer climes. Gets sub zero here, we measure temperature in Celsius. Reading Mike Busch's book on Engines he states you should never start a Lycoming below 32 degrees F. I have my Dynon EMS set up in degrees F and don't start unless temp is at least 40 degrees F. What I am finding is the oil pressure is agonisingly slow to come up. Takes about 30 sec to 40psi. Newish engine, 41 hours, Shell straight 100 oil.
Is this going to harm the engine?
Click to expand...
 
Hornet2008 said:
Hi All. We are experiencing winter in Australia while the lucky people in the north have warmer climes. Gets sub zero here, we measure temperature in Celsius. Reading Mike Busch's book on Engines he states you should never start a Lycoming below 32 degrees F. I have my Dynon EMS set up in degrees F and don't start unless temp is at least 40 degrees F. What I am finding is the oil pressure is agonisingly slow to come up. Takes about 30 sec to 40psi. Newish engine, 41 hours, Shell straight 100 oil.
Is this going to harm the engine?
Click to expand...

100 weight oil is TOO thick for operations in freezing temps. Recommend 20W50 or at least a straight 80 weight. You want the oil to flow well at startup and that 100 weight is like honey at 0 F.

I preheat, via a sump heater, when ambients are below 40* F The colder the temps, the harder the start is on the cylinders. That said, many engines are started without pre-heat in the winter and make it to TBO. IMO it is harder on the cylinders during a startup on warm cylinders that have sat for a month than a cold start on cylinders that have sat 3 days. Cold startings biggest issue is piston wall scuffing which has a very minimal long term effect on a cylinders longevity.

Larry
 
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Generally I fly a couple of times a week, sometimes a week between starts. Don?t always get sub zero temps, try to avoid them but did start this morning at 42 degrees F. Take point on oil and noticed at the oil check it was pretty thick. Not sure what to do with a light globe/bulb.
 
Light

The lightbulb is placed under the cowl. It must be an incandescent type or something else that gives off a lot of heat. Put blankets etc. around your cowl and plug your cowl openings. Allow this to heat the engine for some time. If you have a small micro heater you can also direct the hot air into the cylinders. If you do a search here on the forum, I?m sure you will find lots of remedies that people use. If you get enough cold weather often, you can buy an engine heater that sticks on you oil sump. With that turned on for a few hours, it will preheat your whole engine.
 
I did what Sid outlines.

I also though I saw a picture of a ruptured oil cooler somewhere that sold me on the sump heater.

I also added the cylinder band heaters and a thermostat that I placed inside the cowling.

Of course, this was when i lived in upstate NY...now...well...my enigine never sees less than 80 degrees :D
 
Heat Gun

All great ideas. For my 6 flying days this past year when the temp was below 40, I put my $10 heat gun in to the cowl exit 1 hour before start up. Raised the oil temp to 50+. Using 15W-50 also.
 
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