oil thread

[Chrysopelea]

Having raced cars and motorcycles, where oil is hotly debated, I'm wondering what oil to run in my Rotax, as I JUST received it, and the first thing to do is change the oil, make it fresh so I have a fresh start with my new relationship with my new baby.

I read that Rotaxes use automotive oil, not aviation oil, as the metallurgy is closer to auto than aero.

I know when I raced air cooled Porsches, you could ruin an engine by running most of the "newer" formulations, as they required oil with extra addatives like Zinc and ZDDP.

I've done a quick search, and there doesn't seem to be much info of anyone running any special oils, just the Rotax oil.

I also plan on sending a sample off to Blackstone for evaluation.

Knowing what I know, I know there's a number of regular mineral/dino oils that I ran in my race cars that were FAR superior to regular oils.

I'm wondering if anyone has a preference, or if there's just one oil only to run. I'll be ordering/buying my oil and filter ASAP.

Today I'm going to get a chance to look through the log books and instructional books for my plane, as just yesterday I got my hangar and AOA card, so I can now freely get to my plane and wash/inspect/check out my new plane.

[9Driver]

Lockwood Aviation carries Aeroshell Sport + 4 for the Rotax. This is what I use.

[rvbuilder2002]

Do not use automotive oil.

The recommended oil is very similar to 4 stoke motorcycle oils (the Rotax uses the engine oil to also lube the gear box and clutch just like motorcycles do) and many of them have been used successfully.

One of the problems over the years has been that oil producers often change their formula which in some instances has caused problems in a Rotax that weren't there before.

Because of this, Rotax has worked directly with Aeroshell to formulate an oil specifically for their needs (Aeroshell Sport Plus 4). There are other oils that work, but using them is kind of like a box of chocolates..... you never know what you are going to get (this time).

[mwardle7]

Fluid specifications for the Rotax can be found at flyrotax.com. All of the technical manuals are available under Services>Technical Documentation. I would highly recommend reviewing the Service Information bulletins. There is lots of great information there. The Service Information Bulletin that address oil is SI-912-016. Here's a link: http://docusearch.flyrotax.com/files/pdf/d06038.pdf.

[Sink]

Hi Chrysopelea,

Rotax like motorcycles share the same oil in the engine and gearbox. Automotive engines do not. Automotive oil does not have the same additives that motorcycle oil has in them. Using automotive oil in the Rotax for extended periods will cause extra wear in the gearbox. Automotive oils cannot handle the close tolerance shear forces in a gearbox. Using an automotive oil in this engine will cost you in advertised oil weight properties. As an example if you use an automotive 10-40W oil as soon as you use it in this engine it will drop to a 10-30W. Shear forces and tolerances are too great. Automotive oils don't have ZDDP which is a sacrificial zinc phosphate additive to help coat metal parts. ZDDP will foul automotive catalytic converters.
Aeroshell Sport Plus 4 is a semi synthetic 10-40W which is suitable for most places in the world. Aeroshell Sport Plus 4 is only MFG'd in the U.K. and no place else.

Aeroshell Sport Plus 4 was designed with just the Rotax in mind. The a few years later shell teamed up with a few flight schools that were putting high time hours and their Rotax engines. So they embarked on a new study to determine the properties of their oil versus wear. After the study with thousands of hours Shell mad changes to the base stock and the additive package to better suit the rotax engine. The new red bottled Aeroshell Sport Plus 4 is the new formula.

There are a few other oils that can be considered safe to use and they are motorcycle oils.

If you use 91 oct auto fuel you can use either a full synthetic or a semi synthetic. If you use 100LL most of the time then you must use semi synthetic because a full synthetic will not suspend the lead in the oil and it falls out everywhere in the engine.

Aeroshell Sport Plus 4 just makes it an easy solution to use for either fuel and you know the formula won't change and it was made specifically with your engine in mind.

One place to buy it is:

http://oilstore.stores.yahoo.net/aesppl412li.html

[Piper J3]

I'm using Mobil 1 Racing? 4T 10W-40 with good success...

[rvbuilder2002]

Originally Posted by Piper J3

I'm using Mobil 1 Racing? 4T 10W-40 with good success...

It is one of the oils that was on the recommendations list, before they changed to recommending the Aeroshell only.
It is a fully synthetic oil so use of 100LL should be kept to a minimum.

I have found it to be more expensive than the Sport Plus 4 so there is little advantage to using it instead.

[Piper J3]

Originally Posted by rvbuilder2002

It is one of the oils that was on the recommendations list, before they changed to recommending the Aeroshell only.
It is a fully synthetic oil so use of 100LL should be kept to a minimum.

I have found it to be more expensive than the Sport Plus 4 so there is little advantage to using it instead.

Yes, correct on not using 100LL with the Mobil. I run 93 E10 auto fuel exclusively.

[Chrysopelea]

Thanks for the replies!

I'll order up a case of the Aeroshell sport plus 4 for my new airplane, and just run that.

I know with racing oils is hotly debated, but I'll take your advice and just run what the manufacturer recommends.

That, and a few of the proper Rotax filters with the high pressure bypass valves.

I plan to run only Chevron 91 unleaded, but there might be the occasion where I'm stuck having to run leaded Av-gas, but only if it's absolutely necessary.

I'm going to do everything I can do to avoid running leaded fuel in my plane.

[RFSchaller]

On the plus side if you need oil while on the road you have some chance that the FBO has the Shell aero sport.