Rotax 912 Reliability

[Flyboy66]

What are those of you who operate the Rotax 912 engines seeing for reliability? Has anyone experienced an engine failure? If so, what was the cause?

What about maintenance issues? I have seen some posts about coolant leakage and other things that needed to be addressed, and one person has actually listed the numbers for O rings used in the engines. Am I going to have a box full of O rings in my garage to keep it running? Obviously, no engine will run a lifetime on only oil and gas, but what are you seeing pop up from time to time?

The Rotax Factory video shows the extent of the precision they go to when assembling an engine. Will I be able to perform all maintenance functions without causing other problems because I don't have all the assembly tools they use?

Steve

[Av8r3400]

912 engines are reliable in the extreme. I trust mine with my and my famly's life.

Like any mechanical item there are always things to maintain or repair, but overall they are as good if not better than "certified" aircraft engines.

[Flyboy66]

Good to hear. So I am going to change the question a bit. To those of you who have more than 500 hours on your 100 hp Rotax (carbureted or injected), what type of maintenance or repairs (other than oil, and oil filter change) have you had to perform?

[Floog]

Over 1,200 hours now. Engine still runs better than new! Because I recently converted to EFI, fuel economy is even better now. I've never opened the engine up for anything other than oil changes, plugs, etc. The engine has no leaks. I use mogas primarily and 100LL only rarely. It has never failed to start. It quit running only once: I believe it was vapor lock. The 912 is an amazing and reliable little engine!

[jiott]

I fly a 912uls and have 550 hours on it with nothing other than regular scheduled maintenance. I did have a radiator failure but that is not really a part of the engine and not a Rotax part.

[av8rps]

Besides being known for extreme reliability, the 912 is very well engineered to operate even if you do develop problems. One good example of that is the cooling system. If for some reason you were to lose all your coolant, you can safely fly it to the closest airport, and probably without any engine damage. The coolant system is just cooling the cylinder heads, the rest of the engine relies on cooling fins and air.

[WWhunter]

Floog, you mentioned FI, is this a factory FI engine or an aftermarket type?

As far as getting back OT, my 912 has had ignition problems that may need an entire wiring and ignition module replacement. Not fun to be flying along and the engine start sputtering and totally quit on on ignition. Luckily I was over my strip when it happened. Granted, this is a very low hour (200TT) eninge but of 1997 vintage.

[Floog]

I ordered the factory 912 ULS through Kitfox Aircraft in 2014. EFI is Edge Performance after market kit from Norway. It was essentially a one day conversion. After installing the kit, all that had to be done was set the idle. Later, I added a 40 amp alternator and a backup battery (see pic) for the fuel pumps. The Rotax ignition is stock.
Sorry to hear about your problems.

[tracstarr]

Floog. I just came across the same performance upgrades. Which did you add? Just the intake/Fi system or also turbo and big bore? I'm assuming not the upgraded cam shaft since you said one day conversion. Did you get any measurable HP improvements? Or just what you "notice"? How many hours do you have on it?

I'm curious as I think somewhere I hear them mention a total HP gain of over 50 with everything added. That's pretty damn significant.

I'm just trying to decide which engine to get or if I should wait for the 915is. But, I like the cost savings of the 912uls with bolt ons. Just curious if the reliability is affected with the increased HP

[AirFox]

Give Jason Busat(Canada guy) a call at Badasspowersports.com. He is the North American rep for Edge Performance. Both Doug and I installed the EFI only. It's good for about a 9 HP gain. If I was in the market for a new engine I would order a Rotax 912 ULS from Jason with the Cam, EFI and Big Bore kit. You would save a bunch of weight over the Rotax 915IS. I think that setup would be over 120 HP and more than 30 lb lighter. I have almost 200 hours on my 912 ULS with the EFI. Doug(Floog) has probably even more.

[Esser]

Give Jason Busat(Canada guy) a call at Badasspowersports.com. He is the North American rep for Edge Performance. Both Doug and I installed the EFI only. It's good for about a 9 HP gain. If I was in the market for a new engine I would order a Rotax 912 ULS from Jason with the Cam, EFI and Big Bore kit. You would save a bunch of weight over the Rotax 915IS. I think that setup would be over 120 HP and more than 30 lb lighter. I have almost 200 hours on my 912 ULS with the EFI. Doug(Floog) has probably even more.

Probably save money too depending on if you got a used 912ULS. My 914 has an SDS injection setup. Also a Canadian guy in Calgary. My engine will be easily good for 125. I can run over boost if I wanted too as well since I no longer have to worry about having more boost than fuel pressure. I probably won’t go that route but it’s an option

[tracstarr]

Thanks, yeah, i just noticed the Canadian dealer. I'll probably give him a call in the new year about it.

Originally I was thinking of holding off for the 915is, but I think with this latest discovery (for me) it probably isn't worth it.

[Flyboy66]

I am looking for 100 to 120 hp for $17,000 or less. It looks like a 912uls is the most likely candidate. I have been chatting with the folks at Zipper Big Bore, and I think the only option to get more than 100 hp is a used engine with a Big Bore kit on it, or just getting a new 912uls.

[littlecricket]

Give Jason Busat(Canada guy) a call at Badasspowersports.com. He is the North American rep for Edge Performance. Both Doug and I installed the EFI only. It's good for about a 9 HP gain. If I was in the market for a new engine I would order a Rotax 912 ULS from Jason with the Cam, EFI and Big Bore kit. You would save a bunch of weight over the Rotax 915IS. I think that setup would be over 120 HP and more than 30 lb lighter. I have almost 200 hours on my 912 ULS with the EFI. Doug(Floog) has probably even more.
Scott, if you don’t mind I’m going jump in too. I’m in my research phase... I have been looking at engines leaning toward 912is. While I’ve considered other engines, this is the first that I’ve thought of getting a 912uls reworked engine. Any idea how your EFI compares to the IS? I’m intrigued by the thought of bore kit, cam, and EFI, too. Though I worry about longevity. What about a turbo? Guesses on which firewall forward kit that would go with these setups? Would this be too much for a rookie builder? Things that make me go, hmmmm. Thanks for any added insight.

[Esser]

Scott, if you don’t mind I’m going jump in too. I’m in my research phase... I have been looking at engines leaning toward 912is. While I’ve considered other engines, this is the first that I’ve thought of getting a 912uls reworked engine. Any idea how your EFI compares to the IS? I’m intrigued by the thought of bore kit, cam, and EFI, too. Though I worry about longevity. What about a turbo? Guesses on which firewall forward kit that would go with these setups? Would this be too much for a rookie builder? Things that make me go, hmmmm. Thanks for any added insight.

Mines not flying yet but the aftermarket injection is hands down way more programable and customizable. You can install it on any fire wall forward kit that is standard for your core engine. It’s a lot of info at first but if you can build a plane you can install one of these setups.

[Rodney]

I think that Hal Stockman with Zipper Big Bore has a turbo
Model that goes up to 135 hp

I’ve got the big bore cylinders that go on a 912 ULS
Puts out 114 HP. and believe me it not an “imagined” performance
upgrade.

Hal n Jay are great to work with. Am very pleased with my engine

[Flyboy66]

In one of these threads I saw mention of some aftermarket leaning product for the carbureted engines. Does anyone know what it is and has anyone tried using the product? Did it work as advertised?

[WWhunter]

Hacman is the item you are looking for. No personal experience, but have read many positive posts about it.

[Flyboy66]

Hacman is the item you are looking for. No personal experience, but have read many positive posts about it.

Is there a link or can I just google it?

[Flienlow]

How does the kitfox perform with the 912 in it?

If there is anyone around KPAE, I will fill your tank to find out.

[WWhunter]

Is there a link or can I just google it?

Should be able to Google it. I'm on the road and not able to access my computer right now. Skysports or some ultralight place sells them. If you can't find it. I will find the link and post it. It'll be several days though. Try the search on here also.

[efwd]

I think most will tell you that the Rotax 912 is awesome. I didn't want to have a Rotax at first but when I flew it in Boise I was sold.
Eddie

[Av8r3400]

The Rotax 912 is the benchmark in performance, reliability and economy that all other light aircraft engines aim to become.