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Old 02-12-2012, 11:04 PM   #1
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Default Rotax 912 uls 100 HP TBO

I got kind of a shocking surprise today when talking to two gentlemen who had recently (October) been to the Rotax school to get training on heavy maintenance of the 912 engines. Apparently they were told by the Rotax people at this school that the advertised 2000 hr TBO is kind of a joke for the 100 HP engine. The 80 Hp is very strong and these comments did not apply to it.

They said that about 800 hrs is way more typical, but that people who fly a lot regularly 100 hrs a year or more will get somewhat longer life, but probably not anywhere near 2000 hrs.

This disturbs me a lot, since I have heard nothing about it on this forum and tend to trust the Rotax advertising. I am wondering what kind of TBO experience the forum members are getting, or maybe no-one has put much more than 800 hrs on a 912s yet? I am hoping what these guys were telling me is one isolated opinion from a possibly digruntled Rotax employee.

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Old 02-12-2012, 11:27 PM   #2
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Default Re: Rotax 912 uls 100 HP TBO

Wow. That really surprises me. I know of several 100 hp 912 motors that are running strong at 2000+ hours and have never been touched.
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Old 02-13-2012, 06:23 AM   #3
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Default Re: Rotax 912 uls 100 HP TBO

I sure haven't heard that in the 3 Rotax courses I have attended. In fact at Sebring the instructor,Dean Vogel, told us that the engines showed almost no wear when disassembled at TBO and could probably go longer prior to overhaul.
Of course ,as with all engines, it depends on how long they sit,are treated,maint,etc.
But, I have also heard,as you, (from another source) that the 80 is the better of the two. This I would imagine ,if true, would be because of the lower compression.
In any case,opinions are like a------s.everyone has one.
The 912's have a good track record, I wouldn't worry too much about it
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Old 02-13-2012, 09:53 AM   #4
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Default Re: Rotax 912 uls 100 HP TBO

Thanks for the info. Jiott.

My impression of Rotax is they don't "joke" about anything concerning their aircraft engines.
We have local engines that have way more time on them than I do on my 912uls.
My 912uls is now at 800+ hours and there is no way it needs to be torn down for overhaul. I can't tell the difference now from brand new. It starts easily and runs perfect and that is running almost entirely 100LL Av-Gas through it.
Also, no one I've ever talked to that went through Rotax engine classes has brought back that information. We'll certainly hear from some of them soon.

Will the 912uls live up to the stellar reputation that the 912 has earned? We will soon know as there are tons of them in service. My experience says it already has.

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Old 02-13-2012, 02:53 PM   #5
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Default Re: Rotax 912 uls 100 HP TBO

I know of 9 x 912ULS engines that are used daily (and have been for 4 years) that have hit 2500 hours. None have had any more than routine maintenance.

There are loads of people who seem to like slating the "S". It's a great engine and I would buy another. Power to weight, it's stonking!!
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Last edited by Monocock; 02-13-2012 at 02:57 PM.
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