Unfiltered Auto Fuel

[FrankR]

Has anyone had problems with unfiltered auto fuel in a Rotax 912ULS?

A CFI at the club I belong to convinced the plane's owner to switch to 100LL because of the LSA's were having starvation problems. It seemed to me that the maintenance shop wasn't doing their job.

The CFI is a CFI, CFII, ATP who just added the Light Sport checkout so he could train on the LSA's. I'm not sure he understands LSA's/Rotax. He's not a mechanic.

He convinced the owner that the 30 gallon caddy was unsafe, and 100LL, pumped from the trucks was known quantity.

[roger lee]

Hi Frank,

That CFI doesn't know what he's talking about, isn't a mechanic and doesn't work on Rotax engines from all sources. Have that owner come here or the Rotax-Owner website. 100LL is far worse for that engine than 91 oct. Even Rotax recommended against using 100LL.

If the caddy doesn't have a filter you could add one or pour the fuel from the caddy nozzle through a funnel/filter when fueling.

LSA's aren't having starvation issues from fuel. There have been a couple from poor maintenance, but to my knowledge none have been contributed to solely fuel.
The fuel leaves the wing on most LSA aircraft and go through at least one fuel filter. Then if you have a gascolator that's another filter. Then the fuel pump itself has a fine filter. If you have the red Teflon hoses you have no hose debris. If your plane using any rubber fuel hose after the fuel pump that could be a possible contributor, but if the right hose is used and installed properly that is a very slim chance for an issue.

100LL isn't a fix at all. I have had debris out of 100LL tank truck get in my tank before.

This CFI wants people to be educated on flying so he should also value knowledge about the maint. and care of a Rotax and it's systems before he tries hard to sway people away from doing the right thing to start with.

This CFI has ratings, but is in grade school with LSA for a couple of years until he broadens his education in the LSA & Rotax world.

[FastEddieB]

My Sky Arrow was actually delivered with a "Mr. Funnel" (stock photo):



My mogas always goes through that.

[designrs]

All fuel, either MOGAS or 100LL, that goes into my plane goes through a big red funnel with a screen. It doesn't catch much, but what it does catch doesn't end up in the gascolator or elsewhere.

[Jack Tyler]

Roger's point about filtering auto fuel is a good one and should address your local area's fuel issues, if in fact they exist. The CFI you mentioned could be painting, with a very broad brush, a given problem related to one or more specific gas stations in the area. After all, some gas stations (cum snack shops) have terrible tank maintenance, may not replace their filter media regularly, and might even suffer from tank contamination.

Look at Eddie's fuel funnel carefully and you'll notice the filter media is a green mesh. FWIW I relied on this kind of filter funnel when fueling in 53 countries & island nations over 11 years, from first world locations to some pretty questionable sources in the developing world. The filter media will exclude all water in the fuel, not just sediment. In my experience, the media begins to wear out after a while (perhaps 5 years?) but is cheap insurance and well worth the cost and inconvenience of using it.

[designrs]

Think it's time to upgrade my filter funnel!

[designrs]

While we are on fuel issues... I found this to be the best fuel siphon EVER!
https://www.superjiggler.com/prestashop ... -hose.html

[Nomore767]

The CFI might be the guy doing the instruction but it's the owner that foots the bill for the damage done by 100LL. You don't mention whether the owner, who was persuaded to switch to 100LL, will be using any kind of lead scavenger such as Decalin?

The comments by others here are excellent. The CFI maybe qualified to instruct in an LSA but that qualification should have included instruction in the operation, care and maintenance of the Rotax ULS as well as the different flying characteristics of LSAs compared to regular training aircraft such as Cessna 150s, 172s and Piper Cherokees.

Consider this…will he provide quality instruction in an LSA, not only with flight maneuvers but also regarding the operation and servicing of the Rotax? Our moderator Paul DOES operate such a school and instruction from him/checkout would ensure the student has a good working knowledge of the airplane and the engine.

[MrMorden]

I use 93 octane pump gas (with ethanol) in my CTSW. I don't filter my fuel, and have no problems. I have very little sediment in my fuel, and have never found any water.

But I do use name brand gas from a relatively new station. I wouldn't feel as confident getting no-name gas from a 50 year old station.

[roger lee]

Telling people that LSA aircraft and Rotax engines are having starvation issues due 91 oct. is speaking way out of turn with little knowledge of the entire system in place.

[Jim Stewart]

I use 93 octane pump gas (with ethanol) in my CTSW. I don't filter my fuel, and have no problems. I have very little sediment in my fuel, and have never found any water.

But I do use name brand gas from a relatively new station. I wouldn't feel as confident getting no-name gas from a 50 year old station.

What Andy said. Many years of running mogas. Gascolator has always been real clean at annual time.

[FrankR]

You don't mention whether the owner, who was persuaded to switch to 100LL, will be using any kind of lead scavenger such as Decalin?

Yes, Decalin is in the plane, ready for misuse by renters.

I did notify the Club President about this CFI's "advice" to the owner. He was unaware of this, and none too pleased.

[FrankR]

Gascolator has always been real clean at annual time.

Interesting...

This goes to my theory, about the quality of the service received during 100 hours.

The planes in question both had problems on takeoff, developing full power. No damage, just scary moments.

I'm wondering if, post incident, the Gasolator was even checked.

"Mr. Funnel" looks interesting.

[designrs]

You don't mention whether the owner, who was persuaded to switch to 100LL, will be using any kind of lead scavenger such as Decalin?

Yes, Decalin is in the plane, ready for misuse by renters.

I did notify the Club President about this CFI's "advice" to the owner. He was unaware of this, and none too pleased.

... and then when things start to get screwed up they will blame the LSA and Rotax.
For safety, sanity and a better experience for everyone get an experienced LSA / Rotax advisor in there pronto! Who's your mechanic? The answer should be someone who has been through multiple Rotax courses at Lockwood or Rainbow and is thoroughly familiar with Rotax and has worked on a lot of them. Good luck!

Maybe hire Dr. Paul to come down there and do a few seminars. It would be very worthwhile to get everybody setup and started doing the right things.

[FrankR]

Thanks Rich. My thoughts exactly.

I looked up the shop and mechanic on the CPS website, and he has taken the classes. But...

I have offered to put the owner and club President in contact with some of the experts on this board, at least for a phone conversation. We'll see.