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Engine Oil Warmup Time/Temp

Frankster13

Active Member
Early morning and short taxi left we me wondering about engine warmup time and/or oil temp minimum for takeoff. Is there any info from manufacture? Any rule of thumb?
 
Get the popcorn out

The manual for my engine states the following:

“Engine is warm enough for take-off when the throttle can be opened without the engine faltering.”
 
My personal preference is oil temp up to 100 (however long that takes) before full power takeoff. Might not mean anything to anyone else.
 
100 degrees. It's just what I was taught and re-taught over 50+ years. When cold, I start the engine with the oil cooler shutter closed. Open to halfway once I hit 100 on the ground.
 
Early morning and short taxi left we me wondering about engine warmup time and/or oil temp minimum for takeoff. Is there any info from manufacture? Any rule of thumb?

You will get all sorts of conservative opinions based upon conjecture or hold overs from th radial days. However, the authority on the matter - Lyc, says if the engine does not stumble with application of throttle, it is warm enough for take off. No minimum OT mentioned. Personally, I wait for CHTs to reach 250 to minimize cyl wall scuffing (piston expands faster than cyl wall).
 
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Even living here down in Texas, during the cooler months if I know that I will be flying in the morning, I plug my oil sump heater in the night before. I can be in the 30s or 40s, but as soon as the engine fires and oil starts circulating, my oil temps are around 130 and I am ready to taxi fairly quickly.
 
100 degrees. It's just what I was taught and re-taught over 50+ years. When cold, I start the engine with the oil cooler shutter closed. Open to halfway once I hit 100 on the ground.

Yea, and I was taught to pump the throttle several times with a carb before turning over the engine to prime it. All sorts of bad education out there. The most recent time, when I refused to do it due to the fire risk, resulted in a pretty heated argument where I was called an idiot by the CFI and told to stop reading things on the internet and listen to my teacher. Some of this stuff just won't die. One guy learns it and teaches it to the next guy with no one realizing it doesn't apply anymore or is just plane unsafe. Also taught that leaning will make the engine explode if done wrong, so just don't touch the red knob. was told it was purposely colored red to indicate danger. The list goes on. Shall we discuss Over Square? I am sure we were all taught that will also make the engine blow up. Pretty much the primary focus of complex training. Even have special knob hierarchy to avoid even a second in that state. Yet EVERY fixed pitch prop plane takes off and climbs over square. Sure, this was a big deal in WWII with turbo and super-charged engines, where the risks do exist. NA for naturally aspirated engines.
 
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Manual says

My engine manual for the Superior XPIO-360 says:

“ 4.5.2.5 - Engine is warm enough for take-off when the oil temperature exceeds 75°F and the engine does not hesitate with throttle advancement.”

Seems reasonable to follow the manufacturer’s instructions!
 
Yea, and I was taught to pump the throttle several times with a carb before turning over the engine to prime it. All sorts of bad education out there. The most recent time, when I refused to do it due to the fire risk, resulted in a pretty heated argument where I was called an idiot by the CFI and told to stop reading things on the internet and listen to my teacher. Some of this stuff just won't die. One guy learns it and teaches it to the next guy with no one realizing it doesn't apply anymore or is just plane unsafe. Also taught that leaning will make the engine explode if done wrong, so just don't touch the red knob. was told it was purposely colored red to indicate danger. The list goes on. Shall we discuss Over Square? I am sure we were all taught that will also make the engine blow up. Pretty much the primary focus of complex training. Even have special knob hierarchy to avoid even a second in that state. Yet EVERY fixed pitch prop plane takes off over square. Sure, this was a big deal in WWII with turbo and super-charged engines, where the risks do exist. NA for naturally aspirated engines.

It's just what I do. I realize that it's likely unnecessary and the kind of thing that enlightened pilots rant about (as well as a few other things), but it's not harmful so I've put it way on the back burner of habits to change.
 
If you are running a multi-grade like 15w50 then I would assume you don't need to wait until you have 100 degrees F to take off. I wait for 70F to start taxiing just to ensure that the oil temp sensor is working, 85F for runup, and then takeoff is usually about 90F or warmer.
 
70°F is plenty enough for my engine to takeoff. Sure prefer to burn that gas flying rather than...

Oh wait, my corn starts popping, sorry, gotta go :D
 
Run up and high pressure

I wait until 75F before run up, it never stumbles, and I usually go to takeoff at 92F-100F (a result, not a target). At that temp I don’t get the over 100psi oil alarm. My taxi from the hanger to run up is about 4000’, and I preheat oil (sump pads) to about 50F oil temp at startup.
 
You will get all sorts of conservative opinions based upon conjecture or hold overs from th radial days. However, the authority on the matter - Lyc, says if the engine does not stumble with application of throttle, it is warm enough for take off. No minimum OT mentioned. Personally, I wait for CHTs to reach 250 to minimize cyl wall scuffing (piston expands faster than cyl wall).

Yup, you get all kinds of recommendations from the internet. Here's a fact: I run a Barrett IO-540x and Barrett put the first entry in the log book which says in part: Oil Temp (F) 140 degrees recommended before take off. Barrett must be a quack...:D

-Marc
 
Yup, you get all kinds of recommendations from the internet. Here's a fact: I run a Barrett IO-540x and Barrett put the first entry in the log book which says in part: Oil Temp (F) 140 degrees recommended before take off. Barrett must be a quack...:D

-Marc

I have a lot of respect for Barrett, but am sorry that I do not see that as a reasonable recommendation. Here in the Midwest winters, it would probably take me 45 minutes on the ramp to get to that temperature. I barely get to 160 at full power in those situations. I hold no judgement for others that follow this approach, only suggesting that many different opinions are out there with very little agreement.

BTW, I did not cite random internet opinions. Instead, I quoted a recommendation/guideline from the manufacturer of the engine, which is what the OP requested and is also a fact. So, who do we believe, Lycoming or Barrett? Or skip both and go with the long standing 100* endlessly repeated in hangers across the country. As long as you are unwilling to accept the manufacturers recommendation, it really comes down to which of the various other opinions you choose to accept. I trust that lycoming has tested their recommendation in the lab. I do not trust that my hanger neighbor has done any testing to back up his 100* recommendation.

For others only loosely following this, lyc has recommended oil grades for various ambient temps. They assume you have an oil matched to the ambients for their recommendation to be valid. Meaning there are restrictions if using straight weight oils. SOmeone using 15W50 can get away with much lower OT's than someone using straight 50 weight oil (100 in aviation terms). That is why I chuckle at these generic recommendations that do not account for the oil type being used. 90-100* OT is probably a valid recommendation if running 50 weight oil. There were no mutli-viscosity oils 70 years ago when these guidelines originated. Unfortunately technology changed, but the handed down recommendations didn't.
 
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Yup, you get all kinds of recommendations from the internet. Here's a fact: I run a Barrett IO-540x and Barrett put the first entry in the log book which says in part: Oil Temp (F) 140 degrees recommended before take off. Barrett must be a quack...:D

-Marc

You're killing me here . . . :D

Personally, I use 100F for starting as a mostly met target. No pressure alarm on TO (short taxi)
 
After 25+ years of running a Lycoming engine in my RV-6, I found that the engine typically does not falter when opening the throttle at just about any temperature. Over the years, I have found that my prop cycles smoothly at 70-degrees F with multi-weight oil and at 100-degrees F with straight weight oil.

I am ready to take off at full power when my prop cycles smoothly. Since I use my prefered multi-weight oil, I am ready to go when engine oil temperature reaches 70-degrees F.

Pulling the airplane out of my hangar, I find that I have 70-degree F or more oil temperature when I reach the runup area. Typically my hangar is 40-degrees F or more without running the HVAC.

When the temperature is 32-degrees F (0-degress C) I tend not wanting to fly but I have started my engine at 17-degrees F after being on the ramp over night at Lake Tahoe after a ski trip.
 
what i don't get with 100 or even 140 F min oil temp is the reasoning behind. i understand that we like to avoid high oil pressures that come along with cooler oil but apart from that?

somebody wrote in the checklist of our flying club's archer (homegrown, not from piper) 100F min temperature but nobody could explain to me why. especially in winter the good old piper is idling forever, consuming time/money while creating noise and exhaust fumes and i really wonder what the point of that is.

if the oil pressure is within limits... what does 100F-oil do better than, let's say 50F-oil? in particular with multigrade. it should lubricate, seal, cool, clean and actuate with 50 just as fine as with 100F... or?

i checked the manual of my engine and mr. lycoming itself stated on the subject "if engine feels ok, you're good to go." did not find any specific number. they are very specific on all kinds of things in the manual but not in this regard.
 
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what i don't get with 100 or even 140 F min oil temp is the reasoning behind. i understand that we like to avoid high oil pressures that come along with cooler oil but apart from that?

somebody wrote in the checklist of our flying club's archer (homegrown, not from piper) 100F min temperature but nobody could explain to me why. especially in winter the good old piper is idling forever, consuming time/money while creating noise and exhaust fumes and i really wonder what the point of that is.

if the oil pressure is within limits... what does 100F-oil do better than, let's say 50F-oil? in particular with multigrade. it should lubricate, seal, cool, clean and actuate with 50 just as fine as with 100F... or?

i checked the manual of my engine and mr. lycoming itself stated on the subject "if engine feels ok, you're good to go." did not find any specific number. they are very specific on all kinds of things in the manual but not in this regard.

kind of nailed it. Folks tell you it is mandatory but not a sole can tell you why or where it is written, excluding the barrett advice above and if we follow that then we have all been doing it wrong. Heck, I have had a CFI tell me it is in the manual. You are correct, Lycoming is not bashful about telling you exactly what is or isn't allowed; They even tell you when to pre-heat. Search as much as you like and the best reason you will get is "someone told me to do it." No different than friday the 13th is bad luck. No rationale, but just keeps perpetuating generation after generation. Some people will actually make up a reason to justify following the rule. That is my favorite.

It is my belief that this was a general guideline for radials using 50 weight oil many decades ago and keeps getting passed on. But have no facts to back that up.
 
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what i don't get with 100 or even 140 F min oil temp is the reasoning behind. i understand that we like to avoid high oil pressures that come along with cooler oil but apart from that?

somebody wrote in the checklist of our flying club's archer (homegrown, not from piper) 100F min temperature but nobody could explain to me why. especially in winter the good old piper is idling forever, consuming time/money while creating noise and exhaust fumes and i really wonder what the point of that is.

if the oil pressure is within limits... what does 100F-oil do better than, let's say 50F-oil? in particular with multigrade. it should lubricate, seal, cool, clean and actuate with 50 just as fine as with 100F... or?

i checked the manual of my engine and mr. lycoming itself stated on the subject "if engine feels ok, you're good to go." did not find any specific number. they are very specific on all kinds of things in the manual but not in this regard.

Because 100 is a magic number. Everyone knows that.
 
Because 100 is a magic number. Everyone knows that.

Yep-that's why I warm to that temp before takeoff. That and my oil pressure regulator is not popping off it's seat trying to maintain limits. In theory anyway. I have no data to back this up. I understand 100 deg. F. is a completely arbitrary number. I just feel a little better warming the engine before putting it under load. :)
 
Yea, and I was taught to pump the throttle several times with a carb before turning over the engine to prime it. All sorts of bad education out there. The most recent time, when I refused to do it due to the fire risk, resulted in a pretty heated argument where I was called an idiot by the CFI and told to stop reading things on the internet and listen to my teacher. Some of this stuff just won't die.

You were taught wrong. If you need to prime the motor with the throttle, start cranking the motor first, then use short 2" bursts on the throttle usually 2 to 3 times will do it. This avoids a fire because the motor is sucking it in. If you pump the throttle without spinning the motor, the fuel just drops down on the filter base as a puddle... not good.

When I had my PA28-151 in 1980, I would use the manual prime 3 cycles and then pull 4 blades (mags were always checked at shutoff) that motor would fire on the first blade. And that was with a Prestolite starter with aluminum cable from the back seat battery to the firewall.

I wouldn't mind a manual primer in the RV, I just don't like the copper line.

Sorry for the drift......:eek:
 
Wow, this thread opened up all sorts of strong opinions.

Several people have already mentioned this, but I'll pile on as well. For the IO360, Lycoming specifically says if the engine is warm enough to go to full throttle without stumbling, it's warm enough to fly. There is no published minimum oil temp for flight, assuming correct oil grade is being used.

Having said that, I don't see why I should care if somebody decides to set there own personal minimum higher than that, but just be honest that you're making up your own numbers.

One exception to what I just said; I recently did a 141 prog check for a ppl student who's instructor recently transplanted to KS from WI. He had taught this kid to sit in the runup at 1,800 rpm until the oil temp started to come up.

It's my belief that when you do something like that, you run more risk of abrading the prop or creating other sorts of havoc than you solve by waiting for the oil temp to show some made up number, and I suggested to both of them that he quit doing that....But, much like folks who need a minimum oil temp, thats just my opinion and I don't have data to back it up.
 
Prop cycling

Let's hit all the OWTs in this thread - I only cycle my prop once during the runup.
 
You were taught wrong. If you need to prime the motor with the throttle, start cranking the motor first, then use short 2" bursts on the throttle usually 2 to 3 times will do it. This avoids a fire because the motor is sucking it in. If you pump the throttle without spinning the motor, the fuel just drops down on the filter base as a puddle... not good.

When I had my PA28-151 in 1980, I would use the manual prime 3 cycles and then pull 4 blades (mags were always checked at shutoff) that motor would fire on the first blade. And that was with a Prestolite starter with aluminum cable from the back seat battery to the firewall.

I wouldn't mind a manual primer in the RV, I just don't like the copper line.

Sorry for the drift......:eek:

I am well aware of that and ignored this from the first time that I noticed the carb was vertical. It was just an example of all the bad advice that folks out there get exposed to. I assumed all here knew that was a dangerous practice and would get the reference.
 
Wow, this thread opened up all sorts of strong opinions.

Several people have already mentioned this, but I'll pile on as well. For the IO360, Lycoming specifically says if the engine is warm enough to go to full throttle without stumbling, it's warm enough to fly. There is no published minimum oil temp for flight, assuming correct oil grade is being used.

Having said that, I don't see why I should care if somebody decides to set there own personal minimum higher than that, but just be honest that you're making up your own numbers.

One exception to what I just said; I recently did a 141 prog check for a ppl student who's instructor recently transplanted to KS from WI. He had taught this kid to sit in the runup at 1,800 rpm until the oil temp started to come up.

It's my belief that when you do something like that, you run more risk of abrading the prop or creating other sorts of havoc than you solve by waiting for the oil temp to show some made up number, and I suggested to both of them that he quit doing that....But, much like folks who need a minimum oil temp, thats just my opinion and I don't have data to back it up.

IMHO, it is wise to allow some warm up time in the colder climates. I often fly in wx from 0-20* I set a minimum CHT of 250 before full throttle application. With air cooled engines, the steel cyl barrel can take a bit to warm up to temps. However, the piston is alum and heats up very fast. The differing expansion rates close up the clearance and creates more scuffing. Have no science to back that up, but many of the experts in the old porsche world (air cooled boxer engines just like the Lyc) recommend keeping revs below 4000 until the OT comes up to a certain temp.

Larry
 
Warm up

Finally someone said what’s important, CHT, aluminum pistons, steel cylinders.
Oil temp is great but I have seen the cylinders of operators who are full
Power within 5 to 7 minutes of start up. They can’t understand why they can’t
Make compression and suck oil.
Everyone wants to talk about not chopping the throttle on descent but bring up
Warming there power plant and it’s a different world.
 
kind of nailed it. Folks tell you it is mandatory but not a sole can tell you why or where it is written, excluding the barrett advice above and if we follow that then we have all been doing it wrong. Heck, I have had a CFI tell me it is in the manual. You are correct, Lycoming is not bashful about telling you exactly what is or isn't allowed; They even tell you when to pre-heat. Search as much as you like and the best reason you will get is "someone told me to do it." No different than friday the 13th is bad luck. No rationale, but just keeps perpetuating generation after generation. Some people will actually make up a reason to justify following the rule. That is my favorite.

It is my belief that this was a general guideline for radials using 50 weight oil many decades ago and keeps getting passed on. But have no facts to back that up.

I agree with everything you said EXCEPT the Friday 13 thing. That one is true, I've seen all the movies and something bad always happens on Friday 13th !! :eek::eek::eek:
 
I agree with everything you said EXCEPT the Friday 13 thing. That one is true, I've seen all the movies and something bad always happens on Friday 13th !! :eek::eek::eek:

And that one takes a backseat to "Nothing good ever happens after midnight".

That one's true..
 
And that one takes a backseat to "Nothing good ever happens after midnight".

That one's true..

That seems to be a general truism. Though I can think of a few exceptions in college ;):D Seemed like many good things happened in that timeframe.
 
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