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wadeg
06-27-2008, 10:35 PM
About ready to fire up my 912S.
Even though Rotax publishes a list of recommended oils, what are people using that are the most readily available without having to have them shipped? Looking for one of the ones on the list that can be bought at the auto parts store level (Napa, etc...)
Also, the same question goes for coolant.
Thanks!
Wade
N81WG

RandyL
06-28-2008, 07:35 AM
I'm not a Rotax expert, but from all the reading i've done it looks like any 4-stroke motorcycle oil would be suitable. I'd find your local Honda motorcycle dealer and get some GN4 10w-40.

rockyrim
06-28-2008, 07:54 AM
Hi Wade,
I'm using the Honda oil as well. GN4 10W-40. And a silicate free 50:50
Prestone coolant. My 912S does just fine in 100+ tempertures.
Good Luck
RockyW
S7 912S
N51RD

wadeg
06-28-2008, 10:11 PM
Well, after calling around to many of the motorcycle shops in Portland asking if they carried any of the oils that are listed in Rotax's service documents, I decided to call Schuck's. No motorcycle shops carried the Shell stuff and only one carried Mobil1 (and that was the V-twin oil). Schuck's guy skittered back to the oil and came back to phone saying he had plenty of Mobil1 4T....
Bought a load. Also got some Dex-cool.

This brings me to my next question:

Does Rotax run the engines using Evans or ethyl glycol coolant (Dex-cool)? I understand that to go from antifreeze coolant to Evans, one must flush. If they used Evans in the run-in, do I need to flush before using Dex-cool?

Thanks
Wade Greaves

RandyL
06-29-2008, 10:10 AM
Wade,

Regarding oil, the Mobil 1 4T is a full synthetic. It'll work just fine in the 912 unless you run 100LL fuel. I'm told you want a semi-synthetic blend or regular dino oil so as to better manage the lead that makes its way into the oil system. Even then you'll need to clean out your oil tank regularly to keep the lead at bay. If you're running mogas then no worries, use the 4T, good oil. If you will be running 100LL, and if you have a new engine, I'd use the Honda GN4.

Regarding the coolant, you can use either but you are correct, you must flush thoroughly.

Regarding operting Rotaxes altogether, if you are new to them then I highly recommend this video...
http://www.aircraftspruce.com/catalog/bvpages/rotax912enginevideo.php

I bought one and am glad I did, excellent information. Once I get my engine installed I plan to attend the Lockwood school, but that'll be in '09.

wadeg
06-29-2008, 01:01 PM
Randy,
Surprisingly I have never seen Honda oil on the Rotax service notices. I know the Honda stuff is the best out there and used to use it exclusively when I rode a crotch rocket. Dunno why Rotax doesn't list it.

I plan on using "drug free" mogas. The Staff Jennings on Macadam sells it and is on the way home from work for me. Plan on getting a tank for my truck to load up every once in a while. The good news is that Mulino plans on getting a tank full of the stuff like Lebanon currently has!

I fly an Aeronca Chief and like to mix the juices for the little 65hp.

mickey
09-25-2008, 08:32 PM
I was reading up on this issue yesterday on a Rotax site.

They want you to use oil that does NOT have "friction modifiers" because they'll make the slipper clutch.....slip. (Sounds strange.)

They want to you use oil that DOES have a GL-4 or GL-5 gearbox rating.

That pretty much says "motorcycle oil", but not all motorcycle oils are created equal. The ones they list certainly meet the requirements. I like Amsoil synthetic, personally, and they have a "4-stroke Powersports" oil that is specifically billed as having no friction modifiers and as being good for gearboxes. No info on the "GL-x" issue available on their website, though.

Furthermore, you should use a full synthetic oil if and ONLY if you don't use leaded aviation fuel! Unleaded mogas only.

If you use 100LL on a regular basis you should use a mineral oil or semi-synthetic.

It sounds like the factory recommended oils are the way to go if you don't want to do a lot of research. (Which is why they recommend them, I'd imagine.) They're all available online, and the Mobil 1 is available in just about any cycle shop.

Remember: NO friction modifiers, and you are also lubricating a GEARBOX/transmission. Most off-the-shelf motor oils will fail on both counts.

-mickey

mickey
09-25-2008, 08:40 PM
Oh, and the coolant: Any standard 50/50 glycol/water mix is fine. They recommend straight "Evans Coolant" if your temperatures run high, and they seem to REALLY want you to use that stuff regardless, though they don't come right out and say it.

The benefits of the Evans Coolant include:

1. VERY high boiling point. Damage from "overheating" happens when coolant begins to boil around "hot spots" in the engine. The bubbles quickly disappear again, but that particular spot will get a lot hotter than the rest of the engine. Evans claims that engines can be set up to run MUCH hotter than normal without fear of damage because there will be no local "hot spots."

2. Evans coolant doesn't require high pressure to maintain its high boiling point. Even with zero pressure it still has a higher b.p. than a standard 50/50 mix. That's a neat safety feature if you develop a leak or something. Ordinarily, a loss of pressure means an immediate "boil-over" and complete coolant loss.

3. Evans coolant doesn't need to be changed. Ever. It has no water mixed with it, so there are no corrosion issues to worry about. Normal glycol coolant has additives to prevent engine corrosion, and those additives are gradually used up over time. (Hot water + metal = corrosion, unless there are sacrificial ions in the mix to protect the metal.) Evans coolant needs no such additives because there is no water in the equation.

-mickey

jdmcbean
09-27-2008, 05:32 PM
Regarding Oils... Aeroshell has been an aviation favorite for years. They recently introduced Aeroshell Sport+4 and we (Kitfox Aircraft) will be stocking this oil. Approx $8.00 per Liter (yes they sized in Liters) or $84 case of 12

Aeroshell Sport +4
A premium semi-synthetic multigrade 10W40 oil optimized for use in Light Sport Aircraft four stroke engines. This oil meets or exceeds the requirements of API-SL and all preceding API-S standards, JASO MA, and VW 502.00. AeroShell Oil Sport Plus 4 has been specifically developed fro Rotax Aircraft Engines to statisfy the specific demands of the small 4 cycle piston engines used in the light aviation sector, which have normally relied on automotive lubricants.

AeroShell Oil Sport Plus 4 is unusual in that it is suitable for use with either unleaded fuels or Avgas 100LL as the base oils have been specifically tested to help prevent lead sludging.

DO NOT use AeroShell Oil Sport Plus 4 in engines that are designed to use ashless dispersant aviation piston engine oils such as AeroShell W oils.