Cowl flaps in hot climate
Phillips also make a 20W 50 which I use in winter in an O360.
I don't necessarily disagree with you but what damage/wear is going to be caused by running the engine up above idle before the oil is hot? I don't mean take off power, but say 1500 to speed the warmup? And is a radial any different than a flat engine, supercharger aside.
Bottom line --- how and why you warm up an engine is very dependent on the type and condition of the oil. No way would I use much more than idle rpm until the numbers are "in the green", and where relevant, the oil cooler thermostat is flowing oil through the cooler.
------ supercharger aside.
That's a pretty big "aside", loosing the supercharger ( like Guido Zuccoli in the T-6) is a seriously big deal, although cold oil was not, in this case, the reason for the supercharger bearing lack of oil and the subsequent shearing of the drive).
Other Phillips multi-grade oils are used with great success in the US, but CASA has not approved them here for the likes of the R1820- 86A/86B.
Interestingly, as well as obvious faster time to get the oil pressure up (critical to master rod bearing life) generally the oil consumption is reduced, and there is less of a problem maintaining oil pressure on really hot days.
Tootle pip!!
Last edited by LeadSled; 14th Apr 2015 at 08:52. Reason: typo
Who decided that this could be ignored? I don't know how many 30 year pilots I've flown with have decided that oil temp must be in the green before run-ups or take off.
I was fairly experienced as a grade one instructor at the time. My instructor, who was also the flying school owner and an LAME, insisted the oil temp be in the green before run up. He wasn't interested in what the manufacture POH said about in colder than normal OAT the oil temp may not register a rise until after take off. There was more to come.
After I leveled at 1000 feet after take off, he insisted on a wide circuit and long downwind leg to "allow the engine to cool after the climb at full throttle". Then he really arced up when I reduced power to idle on base for a practice glide approach as he said that would cause shock cooling. He wanted nothing less than 1500 RPM on base and final "to keep the engine warm" OAT was 20C... No closed throttle approaches permitted he said in his Cessna 152.
Jaba,
Tell me, do you think having the oil at working temperature, as recommended by the producer of the oil is another OWT??
Tootle pip!!
PS: I differentiate between what engine manufacturers and oil producers say about their products, versus the airframe manufacturer's AFM. I will generally go with the first two, versus the AFM when it comes to engine operation.
Tell me, do you think having the oil at working temperature, as recommended by the producer of the oil is another OWT??
Tootle pip!!
PS: I differentiate between what engine manufacturers and oil producers say about their products, versus the airframe manufacturer's AFM. I will generally go with the first two, versus the AFM when it comes to engine operation.
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Leadsled,
Can you give me a specific example.
Fundamentally, the measurement and use of oil temperature is an indicator the rest of the engine is at a "suitable temperature" for high power use.
Think of the modern motor car, very good synthetic oils with viscosity index improvers give 5W-50 or 0W-30 kind of oils where as once they were 20W-50 and before that straight mineral oils. Today the car engine goes from start to out the street and "give it the jandel" so to speak. (young Scotty will never live that down).
So my feeling is that the oil temperature you need for a mag check, is not as high as you want for takeoff, but in both cases the numbers are very fuzzy in reality. This is not my area of speciality, but I can see with the use of say Phillips 20W-50 or Shell 15W-50 you can safely apply full power with the oil temperature lower as the effective viscosity is appropriate from a lubrication and pumping point of view.
The next issue is the upper engine components which is referenced to CHT, and here again there is a bit of variation from many OEM's as their is for MAX CHT as there is Min, but I find it hard to taxi out and go without the CHT being in the range of acceptable to all OEM's. On a cold day the oil takes longer to come up, but it does not take long to get to or over 75dF which is a fairly universally accepted minimum for operation above 1200RPM.
As for what the oil producers say…….never paid attention to that but I may be about to learn something. Remember the oil temperature varies depending at what point in the system it is measured. So who knows what the oil companies are referring to. Could well be they are all in the big fuzzy tolerance band of acceptable
By the way….in the APS class there is one topic that is made clear to be off limits….OIL. We suggest buy the one that comes in a bottle colour your wife/kids/neighbour likes, so long as it is a suitable grade aviation oil.
Can you give me a specific example.
Fundamentally, the measurement and use of oil temperature is an indicator the rest of the engine is at a "suitable temperature" for high power use.
Think of the modern motor car, very good synthetic oils with viscosity index improvers give 5W-50 or 0W-30 kind of oils where as once they were 20W-50 and before that straight mineral oils. Today the car engine goes from start to out the street and "give it the jandel" so to speak. (young Scotty will never live that down).
So my feeling is that the oil temperature you need for a mag check, is not as high as you want for takeoff, but in both cases the numbers are very fuzzy in reality. This is not my area of speciality, but I can see with the use of say Phillips 20W-50 or Shell 15W-50 you can safely apply full power with the oil temperature lower as the effective viscosity is appropriate from a lubrication and pumping point of view.
The next issue is the upper engine components which is referenced to CHT, and here again there is a bit of variation from many OEM's as their is for MAX CHT as there is Min, but I find it hard to taxi out and go without the CHT being in the range of acceptable to all OEM's. On a cold day the oil takes longer to come up, but it does not take long to get to or over 75dF which is a fairly universally accepted minimum for operation above 1200RPM.
As for what the oil producers say…….never paid attention to that but I may be about to learn something. Remember the oil temperature varies depending at what point in the system it is measured. So who knows what the oil companies are referring to. Could well be they are all in the big fuzzy tolerance band of acceptable
By the way….in the APS class there is one topic that is made clear to be off limits….OIL. We suggest buy the one that comes in a bottle colour your wife/kids/neighbour likes, so long as it is a suitable grade aviation oil.
We suggest buy the one that comes in a bottle colour your wife/kids/neighbour likes, so long as it is a suitable grade aviation oil.
The two areas in the aviation field where oil characteristics may be different have nothing to do with pretty bottles (or in my case, until recently, 220lt drums) or with viscosity, but are "anti-corrosion additives" and the ability for a film of oil to "stick" to surfaces.
If you have a flat engine with the camshaft above the crankshaft, this will be more significant, re. the "sticking" means the camshaft will still have a measure of surface lubrication until the oil is flowing after start. I am certain we know all the trials and tribulations of Lycoming camshafts and followers.
IN times gone by, a good mate of mine did all the cam regrinds and repairs for several engine overhaulers in the Sydney area ( and many from further afield) and it was rare to see an auto camshaft as badly worn as the "average" Lycoming --- a bump stick with little of the bumps left.
Modern auto oils are, from what I can see, far superior to available aviation oils (even if your engine is "approved" for the few available multi-grades), I guess a matter of market size and demand. We still have plenty of engines around aviation that are not even "theoretically" approved for ash-less dispersant oils.
Further, it still seem to make a difference with aviation oils whether they are a paraffin or olefine base, something that has long since ceased to be an issue with auto oils.
Interestingly, in US, many operators of round engines swear by one of several well known automotive additives, in the hard life of ag. engines, consistently being able to achieve recommended TBO +50% helps keep the cost down.
I better not mention it here, I wouldn't want to encourage criminal behavior amongst those in Australia already committing aviation.
Tootle pip!!
Last edited by LeadSled; 9th Apr 2015 at 14:51.
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Agreed, some are better than others however in my opinion…..and I mean my opinion, the best corrosion inhibitor is CAMGUARD and according to its maker best used with either the straight Shell/Phillips/Castrols or if you want to use a multigrade, the Phillips 20W-50.
Apparently it does not play as nicely with the Shell 15-50, not that it will kill your engine.
I think you missed the humour, whether you use Phillips 100 or Shell 100….its awash. The 100 Plus would be better than the non plus.
I think none are bad, some are a bit better, depending on your requirements. And when it comes to the engines that need 120 grade the choices change a lot.
Apparently it does not play as nicely with the Shell 15-50, not that it will kill your engine.
I think you missed the humour, whether you use Phillips 100 or Shell 100….its awash. The 100 Plus would be better than the non plus.
I think none are bad, some are a bit better, depending on your requirements. And when it comes to the engines that need 120 grade the choices change a lot.
I think none are bad, some are a bit better, depending on your requirements. And when it comes to the engines that need 120 grade the choices change a lot.
Agreed.
Tootle pip!!
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Don't seem to have much choice in mineral oils these days. Mobil used to be good, a very dark rich colour and the 100 was thick. Buy Mobil 100 now and it's lighter in colour and seems to run quicker. Also the newer oil seems to burn more in the same engine.
Synthetic oil I have had no experience with in aircraft, in cars and bikes (Older) it seems to leak more oil when you use synthetic, same in aircraft?
The difference between a flat engine and a radial on a frosty morning was about 15 minutes in warm up time, that's 3 ton on quicker work
Synthetic oil I have had no experience with in aircraft, in cars and bikes (Older) it seems to leak more oil when you use synthetic, same in aircraft?
The difference between a flat engine and a radial on a frosty morning was about 15 minutes in warm up time, that's 3 ton on quicker work
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Information from the Manufacturers to consider.
I know its for cold weather operations but look at the warning notes !!
http://www.tcmlink.com/pdf2/sil03-1.pdf
http://www.lycoming.com/Portals/0/te...20Starting.pdf
From the ten biggest lies about Piston Aircraft Engines..
Lie #3:
Modern multi-viscosity oil offers superior lubrication and longer engine life than old-fashioned single-weight oil.
During the 70s and 80s, there was a dramatic shift from single-weight to multi-viscosity oils by operators of general aviation aircraft...due in large measure to very effective advertising campaigns by Shell and Mobil that touted their multi-vis products (Aeroshell 15W50 and Mobil AV 1) as the greatest aeronautical innovation since the nosewheel.
During the same 20-year period, there was a dramatic increase in premature engine problems in the owner-flown G.A. fleet. It was not a coincidence.
In contrast to "working airplanes" that fly almost every day, most owner-flown airplanes spend most of their lives in the chocks. The biggest enemy of their engines is not inadequate lubrication. It's rust.
Multi-vis oil simply does not provide as effective protection against rust as single-weight oil. The defining characteristic of multi-viscosity oil — the fact that it doesn't thicken up at cool temperatures — makes it a lousy corrosion inhibitor. During periods of disuse, multi-vis oil strips off cylinder walls and cam lobes much more readily than does thick single-weight oil, leaving those parts vulnerable to corrosion, followed by spalling and eventually destruction.
But what about the superior lubricating properties of multi-vis oil? Basically bunk!
It turns out that multi-vis oil is not a better lubricant than single-grade oil. It's actually a bit worse. The reason is that multi-vis oil is made by starting with a thin, single-weight oil stock and adding man-made polymers called "Viscosity Index improvers" that increase viscosity as temperature increases. However, such VI improvers are not lubricants, and their addition actually displaces a certain amount of lubricating base stock (on the order of 10%). In other words, there's more "oil" in a quart of single-weight oil than in a quart of multi-vis.
Now this is no big deal, since the lubrication demands of most piston aircraft engines are rather modest (compared to automobile engines, for example). What is a big deal is the fact that single-weight oil does a better job of protecting engines against rust during period of disuse. That's why we've long recommend single-weight oil for any engine that doesn't fly at least once a week.
Fortunately, after two decades of multi-vis mania, it now appears that more and more G.A. operators are starting to recognize the shortcomings of multi-vis oil and are switching back to single-weight. An increasing number of top-rated overhaul shops are now recommending the use of single-weight oil.
I know its for cold weather operations but look at the warning notes !!
http://www.tcmlink.com/pdf2/sil03-1.pdf
http://www.lycoming.com/Portals/0/te...20Starting.pdf
From the ten biggest lies about Piston Aircraft Engines..
Lie #3:
Modern multi-viscosity oil offers superior lubrication and longer engine life than old-fashioned single-weight oil.
During the 70s and 80s, there was a dramatic shift from single-weight to multi-viscosity oils by operators of general aviation aircraft...due in large measure to very effective advertising campaigns by Shell and Mobil that touted their multi-vis products (Aeroshell 15W50 and Mobil AV 1) as the greatest aeronautical innovation since the nosewheel.
During the same 20-year period, there was a dramatic increase in premature engine problems in the owner-flown G.A. fleet. It was not a coincidence.
In contrast to "working airplanes" that fly almost every day, most owner-flown airplanes spend most of their lives in the chocks. The biggest enemy of their engines is not inadequate lubrication. It's rust.
Multi-vis oil simply does not provide as effective protection against rust as single-weight oil. The defining characteristic of multi-viscosity oil — the fact that it doesn't thicken up at cool temperatures — makes it a lousy corrosion inhibitor. During periods of disuse, multi-vis oil strips off cylinder walls and cam lobes much more readily than does thick single-weight oil, leaving those parts vulnerable to corrosion, followed by spalling and eventually destruction.
But what about the superior lubricating properties of multi-vis oil? Basically bunk!
It turns out that multi-vis oil is not a better lubricant than single-grade oil. It's actually a bit worse. The reason is that multi-vis oil is made by starting with a thin, single-weight oil stock and adding man-made polymers called "Viscosity Index improvers" that increase viscosity as temperature increases. However, such VI improvers are not lubricants, and their addition actually displaces a certain amount of lubricating base stock (on the order of 10%). In other words, there's more "oil" in a quart of single-weight oil than in a quart of multi-vis.
Now this is no big deal, since the lubrication demands of most piston aircraft engines are rather modest (compared to automobile engines, for example). What is a big deal is the fact that single-weight oil does a better job of protecting engines against rust during period of disuse. That's why we've long recommend single-weight oil for any engine that doesn't fly at least once a week.
Fortunately, after two decades of multi-vis mania, it now appears that more and more G.A. operators are starting to recognize the shortcomings of multi-vis oil and are switching back to single-weight. An increasing number of top-rated overhaul shops are now recommending the use of single-weight oil.
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"If you want to see a case study of IO-540 abuse in AC50 Shrikes watch the GAM pilots the country over get cowl flap operation drastically and consistently wrong."
Obidiah
Would you like to explain what exactly you mean by this - just so other pilots do not get cowl flap operation wrong
Obidiah
Would you like to explain what exactly you mean by this - just so other pilots do not get cowl flap operation wrong
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Now this is no big deal, since the lubrication demands of most piston aircraft engines are rather modest (compared to automobile engines, for example).
An interesting post, I take some comfort in it as I pour Aeroshell 100 into thirsty radials and take a good 15 minutes in winter for the oil to get to 40dC even with a bit of preheat
