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Minimum oil temp?

R

rightrudder

Well Known Member
What's a good "green light" oil temperature for takeoff? I know I'm hoping for about 180F in cruise flight, but should I be looking for 120F or so before I take the runway?

Particulars: IO-320 D1A, Catto 70x70 FP prop, standard oil cooler as provided in the finish kit, Aeroshell 50W mineral oil. Thanks!
 
Lycoming says engine is ready as soon as it will accept throttle.

If you wait for 120 F, there will be a line of grumpy pilots behind you.

My personal preference is to see above 90 on the cold days before I start the take off roll but that is totally based on my feelings and not data. In that vein, I dont intend on collecting any data since any relevant collection would include a failure. :eek:
 
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rightrudder said:
What's a good "green light" oil temperature for takeoff? I know I'm hoping for about 180F in cruise flight, but should I be looking for 120F or so before I take the runway?

Particulars: IO-320 D1A, Catto 70x70 FP prop, standard oil cooler as provided in the finish kit, Aeroshell 50W mineral oil. Thanks!
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Using a multi-grade oil will get you in the air faster.
 
For the RV, the EMS manufacturer green lighted my IO-360 at 80deg.F
I am just fine with 75 and CHT's of 200 or better.
 
As a point of reference, the Rotax 912 in a -12 requires 122 deg F before take off. In cool weather, it doesn't get much above that in cruise flight.
 
Just me.

This is just me and not out of a book anyplace. Cold or hot weather I like to give the engine a little time to normalize. Say an idle 900- 1000 RPM till I see 110-120*F of the oil temp. I like to see this temp. before I do a run up and Mag. check. I think I wrote my POHB to say 115-125*, but the idea is to let the engine get lubed and warmed up a little before asking it to come up to full power. I also try to let them cool down and normalize before shut down as well, that is if I am not in very hot weather at the time otherwise, I bring them around the patch at low throttle and cool them while in the pattern. Then shut them down as soon as I can after taxing in. The idea is to allow the engine to heat up and cool down gradually before and after full heat loading. They seem to live a lot longer when your nice to them, just like warm up and cool down before you exercise. Just my two cents here. Yours as always, R.E.A. III #80888
 
Minumum oil temp

I always make sure the oil is at least 100F. before take off. 10-30wt Mobil 1 synthetic. I do most of the warm up in the parking area away from the taxi ways so not to hold up other aircraft. Besides that gives you plenty of time to set up your GPS, radio, altimeter, fit your seat belt, check your charts and plates, make sure everything is where you want it for flight, defroster turned on, drink your coffee, and enjoy the sound of the motor. Then I taxi slow and enjoy the view. This also gives your battery time to recover from sitting and starting , better climb performance without the alternator pulling so hard!
 
I defer takeoff until the OT is 100F, and have set my engine display limits accordingly. The OT bar is red and I get a visible warning until it hits 100F. (I'll taxi when it's 80-85.)
 
What does "when it takes throttle" mean? You can take a cold engine up to full throttle, which obviously isnt good.
 
Robin8er said:
What does "when it takes throttle" mean? You can take a cold engine up to full throttle, which obviously isnt good.
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The Lycoming manual states that the oil temperature is warm enough that you can advance the throttle to full power without it stumbling, or something along those lines.

Don't make me get the manual out.
 
A very good investment is an engine pre heat system.

I've had the full package = sump pads, cylinder rings - and it really presents an engine ready to fly before start.

This time I have a sump pad and oil cooler pad, it works very well at temps down to the 20's, entire engine compartment is around 100F with a blanket over cowl.

In the old days I remember a Cessna manual saying if the temp gage was off the cold peg, go fly. I've also read a mechanics mantra - 180 minimum for take off. Well somewhere in between is a policy that makes sense.

But pre heat probably is best for long engine life. Starting a cold engine below 30 probably has the opposite effect.
 
David-aviator said:
A very good investment is an engine pre heat system.
....
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In Hawaii?

I live in the Carolinas but learned to fly in Michigan. In the warmer regions there is simply no need for an engine pre-heat system. However, there have been times when traveling that I would like to have had some type of pre-heater but even then, there usually isn't a place to plug on in.
 
Pre-heat

I have the full Reiff system (cylinders + sump), a simple necessity here in winter cold in the Midwest. With the cellphone actuated Switchbox, it's wonderful. Under most conditions, a few hours of preheat takes the oil to 70-75F - making my warm-up to 100F before takeoff quick and easy. Not to mention how nicely it starts when all is warm up front. After that, if Old Sol is not warming the cabin thru the bubble canopy, I have seat heaters. Winter ain't so bad after all! :D
 
Keep in mind that too much warming up on the ground can do more damage than good.
With a liquid cooled engine this is not a problem, but our air cooled engines are cowled for proper cooling in flight only.
Excessive ground running does not cool the engine equally. The forward cylinders may get sufficient air, but the rear cylinders don't.
 
oil temperature

Aircraft engine oil will flow sufficiently at room temperature.....70 to 80 degrees. There's no reason to heat the oil higher than 80 degrees to provide better lubrication for the engine. The oil pump can pump it adequately at that temperature. As a matter of fact, it can pump it adequately at 70 degrees. I always idle and lean after start up until my oil reaches 80 degrees. A 10 degree buffer allows the moving metal parts in the engine to warm slightly. It has worked beautifully for over 35 years.
 
Good discussion, guys. I'm thinking, then, 90F and CHTs at 200 or above. Luckily my hangar is at the far corner of the field that's a bit of a ghost town in terms of airplane traffic, so I can run it a bit before taxiing to the run-up area. The taxi itself is so short there's not a lot of time to build temp.

I really like to set a particular parameter here and see the gauge in the green, for that warm fuzzy pilot feeling. :)

I think with SoCal's typically balmy ambient temps that it will be a non-issue during most months.
 
So, Lycoming Recommends Heating

when engine is allowed to get down to +10 to +20 degrees F. I know my Cessna manuals, (Continentals) recommended preheat somewhere below 32 degrees F.

Just saying ---

R.
 
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