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Posted

There was a pretty good article in - I think it was Aviation Consumer - a couple of months ago, about synthetics vs. mineral oil.  The thesis was that synthetics are a good idea for car engines because they don't break down over a 10,000 mile oil change interval, but barring breakdown of the oil, mineral oil does as good a job of lubrication as synthetics.  But aircraft engines go only 25-50 hours between changes, so no need to pay the higher price for synthetics because the oil will not be in the engine long enough for breakdown to be an issue.   

Posted

Panther,


First, I fly a Bravo with Aeroshell and camguard.  Don't have any temp problems even at altitude.  I can probably credit that to a real good job of baffling.  If you have temp problems, that is the first thing to check.  On the other hand, let me relate a past experience with high engine/oil temps and synthetics.


Back in the 80's, I flew the world's best airplane (seriously) a Beech Twin Bonanza.  Had to have the seats and weight capacity for hauling engineers around to job sites related to construction business.  Flew the airplane the first two years and about 400 hours.  Logged every quart of oil, every gallon of gas, and performance perameters in a flight log.  Always had an issue with high oil temps on climb outs and in summer even at cruise they might stay up around 200-210.  Engines each used about a quart of oil every four hours and burned 30 gallons block to block.  


My mechanic suggested that I switch to pure synthetic and said he expected it to decrese my oil consumption.  Because of high oil temps, we were also changing oil about every 15-20 hours.  Went to pure synthetic {don't remember the brand, Phillips I think}.  Kept logging every flight, every quart of oil, every gallon of gas, all performance perameters.  I changed nothing about the way I flew the airplane or the power settings.


With the synthetic, I never saw over 190 degrees even on climb out.  Fuel burn dropped to 27 gph and oil consumption decreased to one quart every 8-10 hours on each engine.  Stayed that way until I made the mistake of trading for a new Bonanza several years later.  Some bogus lawyer brought a class action suit against the oil manufacturer around 1994 alleging that the synthetic damaged some engines due to sludge.  I don't believe it, but they took the pure synthetics off the market.


If the pure synthetics are back on the market, I would be tempted to go back to using them.  On the other hand, my Bravo flies beautifully, squawk free and about 8 knots over book (almost Acclaim speeds) at all power settings and altitudes and does that at gross weight, one quart every 10 hours, and on-book fuel consumption so I don't have much incentive to do anything else.


You might try the synthetics if you have a real need to be addressed.


Don't know if this helped, but as my grandmother used to say, "Even a fool says something right every now and then".


John Green


 

  • Like 1
Posted

its a well-known fact that synthetic oil cannot dissolve or carry lead.  Other thah that, I would use it.  Aeroshell 15W50 is semi-synthetic, I think 50%.  We switched to W100 with Camguard.

Posted

If you fly it often i dont think there is a bad oil.  Lots of people are going to W100 or Philips X/C with camguard because if it sits over 10-14 days, the cam and lifters start pitting.  straight oil and camguard seem to delay this action.

Posted

Quote: jetdriven

If you fly it often i dont think there is a bad oil.  Lots of people are going to W100 or Philips X/C with camguard because if it sits over 10-14 days, the cam and lifters start pitting.  straight oil and camguard seem to delay this action.

Posted

You know, I think all the oils today are really good.  I doubt seriously that the weight or type of the oil makes alot of difference these days.  The data appears to indicate that the addition of Camguard is helpful where the plane is not flown alot.  I see recommendations for 100 in turbos because of the "heat," but turbos are not significantly hotter than normally aspirated, and in fact if you fly a turbo in the flight levels, it is going to spend alot of its flying life at temps below 0 C, rather than the warmer temps lower down.  What makes the most sense to me is to use an oil for a turbo that covers a broad range of viscosity. 

Posted

borrowed from ths forum: http://www.vansairforce.com/community/showthread.php?t=76408


these guys are pretty good reading.  


The referenced webinar "all about oil"  is found here:  http://cloud.savvymx.com/index.php/webinar


 


I am a huge fan of Mike Busch.  He is accurate, scientific, and goes against much of the GA old wives tales we all know.


 


here is the text borrowed





Default"All About Oil" Webinar summary



I listened in on the "all About Oil" webinar the other evening that was presented by Mike Busch, of "Savvy Aviator" fame - Google and check him out if you are not familiar with his credentials. Thought I would pass along some highlights from his presentation:

OIL TYPES
Mineral (petroleum-based) oil is better than synthetic oils with respect to suspension of particuates, and also seals better

Synthetic oils have superior (less) friction characteristics and are longer lasting than mineral oil.

As long as we are relying primarily on leaded avagas, we cant take advanage of the benefits of synthetic oils. Our engines run rather dirty, and the oil has to be drained often to get rid of lead and particulates. Also, the superior lubricity offered by synthetics is less important in piston aircraft due to the relatively large clearances and slow RPM compared to turbine engines.

Multigrade oil offers faster lubing during cold starts.

Monograde oil offers better corrosion protection, as it is not as thin at room temperatures and will stay on parts longer.

Corrosion is the #1 reason for failure to make TBO. There is very little wear during steady-state flight conditions. The longer an engine sits between starts, the more wear/corrosion will occur due to lack of oil on mvoing parts. Engines are typically not worn out, they are rusted out! Therefore, monograde oil is preferred over multigrade unless you anticipate unpreheated, subfreezing cold starts. Alternatively, you could use multigrade in the cold season only.

Aeroshell W100 is the recommended monograde; Phillips x/c 20W-50 for multigrade use

Aeroshell 15W50 is specifically NOT recommended; this is a 50% synthetic blend and will not be as effective in suspending/removing particulates

ADDITIVES
Ashless dispersants (AD oils) are in oils to suspend particulates. There is no evidence to indicate that engines do not break-in as well using AD oils.

"Microlon" / /"Slick 50" NOT recommended; a Teflon product that is potentially harmful according to a NASA study. Dupont, where Teflon wasdiscovered has specifically said that Teflon should not be used in oil

"Avblend": no harm, but no demonstrated benefit either

"ASL Camguard": Recommended! Some reduction in wear, but very effective in reducing corrosion, even more so than the additives that are included in the Aerosehll Plus and Exxon oils, although those are good as well.

"Lycoming 16702": An antiscuff, boundary layer additive, same as used in the Shell 15W-50/Exxon Elite products. Effective, although Mike prefers Camguard. Regardless, if you are using the Phillips x/c 20W-50 oil, use either Camguard or the 16702 additive.

"Marvel Mystery Oil": Some effectiveness in unsticking valve lifters and not harmful, but otherwise not recommended as a standard additive.

OIL LEVEL and CONSUMPTION
"normal" consumption is quite variable; 1 qt in 4-20 hours is fine; do not want less than this as it may mean oil is not circulating properly. No advantage to having full oil. Pay attention to changes in oil consumption however, as this could mean future problems

All engines will run fine at half of maximum oil capacity, and most at less than half. 2/3 capacity, or 5-6 qts in an 8 qt engine is recommended (8 qts in a 12 qt engine; 1 additional qt if your oil consumption is high.

Air-oil separators are NOT recommended; they can hide important symptoms regarding oil consumption and also makes it hard for engine to purge itself of acids etc.

OIL CHANGES
If using spin-on oil filter, change oil at no more than 50 hrs or 4 months; change at 25 hrs or 4 months if only using a oil screen. If significant metal found at oil change, reduce to 15-20 hr intervals.

Try to not let the engine sit with dirty, old oil; change it before a period of disuse rather than after.

Cut open the oil filter at every oil change or least at each annual. A small quantity of metal, approximately 1/8 tsp. or less is normal; more than this should be investigated further

If significant metal is found, send in to lab for analysis (about $100). Aviation Laboratories in Kenner, LA is recommended.

Oil analysis for microscopic wear metals can provide early warning of wear events. Blackstone Labs in Ft. Wayne, Indiana is recommended.

GENERAL:
Ideal oil temperature is 180-200F; definitely want it above 170 to boil off water. Temperature on gauge is typically the temperature of the oil during the coldest part of its circulation cycle; temperature is typically about 40 degrees higher at hottest part of cycle, hence the above 170 requirement. Since water boiling temperature decreases at higher elevations, lower temperatures may be ok at altitude.

If engine not to be run for 6 months or more, a preservative oil ("pickleing oil") is recommended. Fill sump with preservative oil; fly or run up engine and then shut down. Install dessicant plugs and place dessicant bags in air intakes and exhaust.

Pre-heating of engine to minimize wear at startup should be done any time temp is at 32F or lower. Starting without preheat at 20F or lower is a very severe wear event.

Lycomings are susceptible to wear on cams and lifters due to their high position on engine and difficulty in getting oil to these parts. Use of a Nay Nozzle (sp?) that squirts oil on cam shaft can help this. Installation of the nozzle would have to be done at engine build or upon tear down, but is relatively cheap and worthwhile.

Next webinar: "All About Cylinders", October 5 (free)
http://www.savvymx.com/webinar

Mike can be reached for questions at mike.busch@savvyaviator.com

regards
erich
  • Like 1
  • 2 weeks later...
Posted

Quote: johnggreen

Panther,

First, I fly a Bravo with Aeroshell and camguard.  Don't have any temp problems even at altitude.  I can probably credit that to a real good job of baffling.  If you have temp problems, that is the first thing to check.  On the other hand, let me relate a past experience with high engine/oil temps and synthetics.

Back in the 80's, I flew the world's best airplane (seriously) a Beech Twin Bonanza.  Had to have the seats and weight capacity for hauling engineers around to job sites related to construction business.  Flew the airplane the first two years and about 400 hours.  Logged every quart of oil, every gallon of gas, and performance perameters in a flight log.  Always had an issue with high oil temps on climb outs and in summer even at cruise they might stay up around 200-210.  Engines each used about a quart of oil every four hours and burned 30 gallons block to block.  

My mechanic suggested that I switch to pure synthetic and said he expected it to decrese my oil consumption.  Because of high oil temps, we were also changing oil about every 15-20 hours.  Went to pure synthetic {don't remember the brand, Phillips I think}.  Kept logging every flight, every quart of oil, every gallon of gas, all performance perameters.  I changed nothing about the way I flew the airplane or the power settings.

With the synthetic, I never saw over 190 degrees even on climb out.  Fuel burn dropped to 27 gph and oil consumption decreased to one quart every 8-10 hours on each engine.  Stayed that way until I made the mistake of trading for a new Bonanza several years later.  Some bogus lawyer brought a class action suit against the oil manufacturer around 1994 alleging that the synthetic damaged some engines due to sludge.  I don't believe it, but they took the pure synthetics off the market.

If the pure synthetics are back on the market, I would be tempted to go back to using them.  On the other hand, my Bravo flies beautifully, squawk free and about 8 knots over book (almost Acclaim speeds) at all power settings and altitudes and does that at gross weight, one quart every 10 hours, and on-book fuel consumption so I don't have much incentive to do anything else.

You might try the synthetics if you have a real need to be addressed.

Don't know if this helped, but as my grandmother used to say, "Even a fool says something right every now and then".

John Green

 

  • 4 years later...
Posted

Have there been any updates to the information relating to the use of Camguard in a TSIO-360? Right now, I'm planning to run X/C 20W50 plus Camguard in my 252...

  • 3 weeks later...
  • 2 weeks later...
Posted

The concern about synthetics not holding lead in solution only applied to Mobil 1  a pure synthetic.  For those of us who ran Mobil 1 (pure synthetic)  in the Mooney's it was a disaster.  We had run full synthetics in race cars which get overhauls at about the oil change interval for a Mooney. 

We did not fully appreciate the significance of it at the time but we ran a wet sump Mazda for about 50 hour including Daytona 24 hour,  shipped the car back to CA for work and the first time they fired the engine the oil pump sheared and there was a layer of thick gel in the sump ( mixture of lead and synthetic where the lead had settled out)

However, synthetics ( both mixtures and pure synthetic) are used in race cars where there is a very short engine life and short oil change interval.  Had good results with it in my MB motor after getting a settlement from Mobil for the Mobil AV oil damage.

Other  aviation semi synthetics work just fine

Turbo motors put a lot of stress on the motor as it is normally run 65-75% power and high altitude   and they run hot.  Turbos need a non coking oil

 

Posted

I just run 100 W

the inside of my engine looks great!

Shell says to change your oil at least every 4 months. If you do that, you could probably run canola oil without issue. 

If you spent as much time flying as talking about oil your engine would be better off.

 

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