The engine oil war

I hereby cast the first stone to start the engine-oil war. This war will be similar to the primer war in that people may state their opinion without any facts to back it up. We have all heard old wives tales like:
Never go swimming within an hour after eating or you will get cramps and drown.
Turn off avionics before starting the engine because the starter will produce a damaging voltage spike.
Motorcycle oil is higher quality than car oil.
Just because people have always said something does not necessarily make it true. Is motorcycle oil really better than car oil? The Rotax engine manual says to use name brand motorcycle oil. Has the Rotax company run engines on both car oil and motorcycle oil and determined that the gears wear out quicker on car oil? Or is Rotax a victim of motorcycle manufacture's hype? Whatever is printed on the back of the oil containers can not be believed anymore than the words on the back of snake oil bottles that are sold at a carnival. Have the oil makers published any test day to confirm their claims?
Here are links to a couple of articles that cast doubt on the superiority of motorcycle oil:
http://www.nightrider.com/biketech/oiltest1.htm
http://www.vfrworld.com/tex_vfr/tech/oil.htm
The first article has test data that indicates Castrol GTX is superior to motorcycle oil. I have been told that synthetic oil should not be used for break-in or for use with leaded fuel. Keep in mind that I am NOT recommending the use of any particular oil. I only offer the links to articles that may be of interest to those contemplating the purchase of oil for their Rotax engine.
Pick your side and let the war begin! LOL
Joe

Aeroshell

I plan to use the new Aeroshell Sport Plus 4 oil. It is approved for the Rotax 912 by Rotax and was designed specifically for these engines. The fact that it is relatively new does not bother me- I figure Aeroshell knows what they are doing when they formulate an oil.

Jeff

Mich48041 said:

Is motorcycle oil really better than car oil?
Pick your side and let the war begin! LOL
Joe

Click to expand...

It sounds like the argument you are trying to make should go both ways...why don't motorcycle owners just buy car oil? It is a lot cheaper. It is simply because they are totally different formulations intended for totally different applications. If the argument presented in these articles you linked too was valid, then people should also be doing it with cars. For many years it has been standard practice for even manual transmissions to use automatic transmission fluid. Why? Because it is specifically formulated for applications where gears are involved. Using engine oil would be a lot simpler and less expensive. I don't think teh logic presented in these articals would hold up very well though.
The early origins of the Rotax company (actually the parent company Bombardier) was in the design and production of gear boxes and power transfer devices...before they ever made their first engine.
I think they know what they are doing when it comes to the required oil for their gear box.

Like Scott said is the gear lubrication "package" available in motor cycle oils that the 912 needs. For years finding an oil that met the specs that Rotax demanded ("API SF or SG") was tough in the US. Today, Shell has made it easy with Sport Plus 4, or CPS (California Power Supply) has a semi synthetic oil formulated for Rotax 912's also called AV-9.

http://www.rotaxparts.net/scripts/prodView.asp?idproduct=649

No wars needed, just good information to make good decisions. If you want to start a war lets talk about healthcare.

if you have time ...

If you have about 30 minutes go to this sight, I believe its free and sign up for a free trial run of Rotax info course by Phil Lockwood of Lockwood Aviation discussing the Rotax engine. There's even a little test at the end if you care to take it. ByDanJohnson.com (in an older blog than listed on the first page) states after this trial period this free course will sell for $49.95

Go to this page, sign up and take the free course (I believe there is no charge ... correct me if I'm wrong)
There was so much info I had to take notes.


Enroll to see free Rotax course CLICK HERE ... then go to create an account.

Click Here to go to ByDanJohnson.com ... search thru older blogs at bottom of page to see description of course.

Enjoy and Learn ... I did.

Oil? How much?

+1 on the formulation for gears. If the crankcase oil is also used to lube the gearbox, then it should be formulated for such use.

I ran Shell Rotella in Ole 84 for a time, but it was very smelly. Practically reduced the 'chick magnet factor' of that plane to zero. I doubt the current coat of red paint would reverse the effects of that smell.

Now, synth oil CAN be formulated to tolerate lead -- Amsoil is one of those dispersant types. Amsoil is also an ashless oil, so use in piston aircraft engines is OK, but the manufacturer will not condone such use -- liability, you know.

I mix 25% Amsoil with Phillips X-CY in my 550, and it seems happy with the stuff. But, the only scientific data point that I can see is that this oil attracts bugs -- I get 'em all over the leading edges of the plane when I fly. I experimented with no oil in the engine (of course, this stops any flying activities), and sure enough, no bugs were splatted on the leading edges.

The again, I used to fly a Champ, and it seemed to have about the same amount of bugs on the trailing edges as the leading edges, proving that whatever oil the bugs were using allowed 'em to go faster than the Champ! I gotta find out what that stuff is!

If that ain't a shot across the bow, I don't know what is!

"**** the torpedoes! Full speed ahead!"

Carry on!
Mark

Time for an anecdote.

Verdean Hiner used to test fly & deliver for Aviat and they used to use 15W-50 A/S. Brand new Christen Eagle. Low pass at 200 plus. Sharp pull up at the end of the runway and the front main grabbed & the prop stopped. Deadstick home, push it back in the shop. Couple weeks later, a brand new S-2 Pitts with same AEIO (EIEIO) engine. Low pass at 200 plus. Sharp pull up at the end of the runway and..... the front main grabbed & the prop stopped. Deadstick home again. They switched to W100 and haven't been able to make it happen again. Was it bad engines or is it the oil?

My real job is blending and selling lubricants. Our company is PetroBlend, we are an independent lubricant manufacturer and we build products for nearly all automotive and Heavy-duty applications, on and off highway.

Much like flying everything in oil formulation is a compromise. What is causing problems with current PCMO,(passenger car motor oils) is this. The new cars all have low wear designs and the auto builders have demanded that the anti-wear additives be reduced in the current engine oils. These oil perform wonderfully in modern motors, with roller cam followers and all the wear areas eliminated. This oils will take these engines to multiple hundreds of thousands of miles with minimal maintenance. The current oils are the right products for the current engines.

They are NOT the correct oils for legacy engines like a hopped up small block with stiff valve springs. These engines need ZDDP (zinc-dithiodyakyldiphosphate) This is the primary component of anti-wear additives in most motor oils. The car builders believe that ZDDP will poison their catalytic converters so they have mandated it to be reduced to a very minimal level. Plenty for the current engines, but not nearly enough for a legacy engine, especially a hot rod, or a gasoline farm tractor, or an old truck.

I am not an expert on the Rotax but my guess is that it has an appetite for anti-wear additives and the current crop of engine oils are not the best choice.

For these older motors people should be using "hi-mileage" engine oils, or a low-TBN Diesel engine oil. The diesel engine oils are loaded with anti-wear and all other kinds of good stuff, too much actually for a gasoline engine, but if it doesnt burn oil, it will work fine. If it burns oil, then the additives can cause ring sticking which is not good either.

I realize this is a long answer to the original question, but to answer the question, "what oil is best" requires knowing what engine it is going in, because the answer is, "It depends."

ZDDP is not your friend in traditional Ly-Cons because the temperatures in the valve areas is too hot for the ZDDP additives. They come apart into some very nasty compounds that are acidic and will cause horrible deposits in your engine. I told Mark to dump the Rotella from -84 when he told me he was doing that. Bad idea...

Tailwinds,
Doug Rozendaal

F1Boss said:

I ran Shell Rotella in Ole 84 for a time, but it was very smelly. Practically reduced the 'chick magnet factor' of that plane to zero. I doubt the current coat of red paint would reverse the effects of that smell.

Mark

Click to expand...

Mark - Are you saying my truck stinks??

neal

Motorcycle Anecdote

Many moons ago when I was attending college in Minnesota, I had a little 400cc Honda motorbike that was my main vehicle. I just used regular motorcycle oil in it. This which worked fine until one day, right after an oil change, I took a hard run from the twin cities to Bayfield Wisconsin on a hot summer day. I noticed as I pulled into town that the motorcycle did not sound right. When I checked the oil, it had the viscosity of water.

On my mechanic's advice, I switched to Golden Spectro.

Later that summer I made an even harder run up to Grand Forks North Dakota, and I still had oil that was like oil when I arrived.

Hans

Doug (B25), that's a nice post.

n8zg said:

Mark - Are you saying my truck stinks??

neal

Click to expand...

The smell came from the ZDDP being destroyed by the heat in the valve train... around the exhaust valve guides specifically.... Your diesel truck oil probably never gets above 200F.

The oil temp on the gauge in your Lycon is the coolest temperature in the system. in localized areas in the cylinder heads the oil might reach the mid 400s in climb and the ZDDP becomes unstable in that range....

The oil in a water-cooled Rotaz is much more like a car or truck engine where the temperatures are much more effectively regulated.

Tailwinds,
Doug Rozendaal

For what it's worth,
I know only one or two people who've actually run a 912 from new to TBO. One of those ran 2 912's to TBO (one an 80hp, the other a 100hp) - he does a lot of long grinding xcountries back and forth across the CONUS - and already has a few hundred hours on the third one.

He uses Shell Rotalla 10W-40 (API grade SJ I believe) semi-synth oil (and Fram oil filters) from his local auto parts stores exclusively.

He reported that both engines still ran normally and had normal compressions, clean mag plugs, etc., when he pulled them.

Don't know if that really means anything, but there it is.

I use the Aeroshell sport 4 in my 912uls, but was using Valvoline 10w-40 auto oil before. I'm at about 400 hours on mine with no problems. Compressions are about an inch down (i.e. 86/87 at annual about a month ago) on all cyls and the mag plug comes out clean at every oil change.

I tend to be superstitious and use what Rotax recommends (thats why I've gone to the aeroshell) but it's hard to argue with the other oils being used without problems.

We'd probably have to go to a dealer who sees a lot of engines near TBO with good records of what oils were used, when they were changed, etc. to really get any meaningful data on this. In the meanwhile, as long as it meets the weight and service grade requirements of the engine, it should be fine..

LS

smelly chick repellant

B25Flyer said:

The smell came from the ZDDP being destroyed by the heat in the valve train... around the exhaust valve guides specifically.... Your diesel truck oil probably never gets above 200F.

The oil temp on the gauge in your Lycon is the coolest temperature in the system. in localized areas in the cylinder heads the oil might reach the mid 400s in climb and the ZDDP becomes unstable in that range....

The oil in a water-cooled Rotaz is much more like a car or truck engine where the temperatures are much more effectively regulated.

Tailwinds,
Doug Rozendaal

Click to expand...

Hey Doug:

I could only smell it on short final and taxi in, so your reasoning is probably correct. I would run the women off the ramp after shut down. YMMV with the new paint and correct oil, of course.

Carry on!
Mark