I have always just used whatever turbine oil the MFG suggested on whatever engine i had at the time. But, just a question is there REALLY any difference between the Aeroshell 500, BP 2380 or Mobil II other than the Price?? Russ

There are many widely spread opinions about this, but the fact is: if it's full synthetic oil it will work, even if it's intended for automotive use.
In fact there has been a long term test of running a turbine on diesel fuel without any oil here in germany. The bearings did not care much for it, the running surfaces held up to the tests. (I'm not saying you should do it, just that it will work WITH DIESEL).
You can spend hours of discussion on what oil to use, and wether to use 3,6% or 3,9%....but in the end you'll be fine with whatever you do.

Just my experiences
Hank

anyone using Quicksilver outboard oil yet?

It seems like its the same as Mobil 254 but only $3 a quart

Tar Baby..

...500, 2380, MBJII are all something like 97% the same, its only the manufacturers base oil addative package that diferentiates them slightly.....by the time we've diluted them down further...well, the difference is'nt even worth typing about... Personally, having spent several years in the oil reaserch buisiness i wouldnt really use the Steam Turbine or 2 stroke oils which have totally different lubrication properties completley...just my threepennybits worf...

This has been cussed and discussed numerous times in this forum.
IMHO, the simplest thing to say is:

Make sure that what ever turbine oil brand you use, that it is in compliance with MIL-PRF-23699(B) (or later suffix). Look it up on the web.

Mobil Jet II, Mobil Jet 254, Aeroshell 500, BP or Exxon 2380, Castrol turbine oil, all qualify and are all fine turbine oils for our purpose.
In 1999, Exxon sold the rights to all of their aviation oils to BP. That is why I have seen some confusion on which is which on this forum. They are chemically identical.
Any or all of these can be obtained in every area of the country.

Try www.oil-store.com for your favorite at competative prices.

JetCat recommends Aeroshell 500, as it seems to not "coke" the vaporization tubes and the combustor as much as other oils seem to.

I have heard, but cannot confirm, that Mobil 254 will permanently stains your paint job.

Harley Condra
BVM REP
JetCat REP

been using 254 for two years now without issues.

I sent my T-500 in for servicing and asked what the insides looked like and they told me everything looked perfect. So 254 must be ok.

what do you mean by cokeing the vap. tubes, making them black and dirty?? If i acutally NEED the shell 500 for the jetcat it is not a problem paying for it, i just hate too when the mobil is so much cheaper.. Russ

Tar baby,
Coking may not be the most accurate term, but most of us use it, cause most of us (me included) are not chemical engineers.
The vaporization tubes are tubes through which the injection needles pass through. The injection tubes are sometimes referred to as "sticks', when in fact they are hypodermic sized stailess steel or maybe by now, inconel tubes. A tube is always hollow, but a stick might not be.
There is also a heating tube through which the injection tubes are passed which provide a heating area surrounding the injection tubes in order to promote complete vaporization of the jet fuel prior to it's reaching the combustion zone. You may have heard some engines that, while at idle RPM, make "snapping" or "popping" sounds. That may be caused by incomplete vaporization, and the sound is from fuel droplets exploding in the comustor. As the RPM is increased, the temperature is too, and the fuel is then completely vaporized. No more "popping".

The tubes also enable the engine manufacturer to "Tune" the engine. In other words, they can move the injection tubes around, by careful bending of the tubes, changing the angles at which the fuel vapor is admitted into the combustion zone, in order to have a flame front that is constant around the diameter of the combustion zone. Even combustion around the entire inner surface of the combustor is what must be done in order to avoid hot spots in the combustor. Maximum combustor/engine life, and good power is what the whole thing is all about. Just like a gas stove burner, in theory. All of the flames must be even in length, and the correct color.

Anyway, some folks say that the combustion by-product-crud-*&^%#@*^ found in the combustion zone and on the tubes, sticks, or whatever you choose to call them, is "Coke".
Coke is either Coca-Cola, an illegal substance some put in their noses, or as the term is used in the steel or metal alloying industry, a fuel made from the heating of bituminous coal in a furnace and a distillation process. It burns at a much higher temperature than the coal from which it is produced.

The black crud in our combustor area may not really be "coke", but I don't care. I use the term cause everyone else does.
Some think, or believe that 2380 forms more "coke" in our engines than some other oils do. That's okay with me too. I am using 2380 right now, as I got one heck of a deal on it at my local FBO.

Jetcat recommends Aeroshell 500, as well as AMT USA. In they're opinions, it is better oil for that reason as well as other reasons.
That's fine too. I believe their recommendations. I have used many of the oils, and feel that they are all good and they are all useable, as long as they comply with MIL-PRF-23699.
If anyone disagrees with me on this issue, that's fine too. I get very good bearing life in my JetCats.


Harley Condra
BVM REP
JetCat REP

About "coking":

I think coking is the correct term. I spent a few years working at a refinery here in Houston - where there is a massive coking unit. After all the different fractions are squeezed out of a barrell of oil, they send the junk that's left over to the coking unit to pressure cook down into "coke", which comes out much like coal and is then sent to a cogeneration station to be burned for power for the refinery like coal. The coking unit is N-A-S-T-Y. The coke dust is very fine and gets into everything. They pay the operators extra to work the unit. I vividly remember talking to an operator who was telling me that, despite the high pressure showers they had, he would go home play tennis and "sweat black junk".

I stayed away from the place.