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Rotax 912 ULS Break In

E

Ex Bonanza Bucko

Well Known Member
I have a new S-LSA with the Rotax 912 ULS in it. I can't find any documentation about break in procedures or times in the Rotax or RV12 books. The oil temp at 5000 RPM cruise on a warm day (82F) is right up at the caution mark....266F.

What should I expect about this?

Thanks,
EBB
 
To my knowlegde, Rotax has not published a break-in procedure for the 912. Per the POH....

Oil Temperature
Minimum 122° F
Normal in Cruise 190° to 230° F
Caution Range (yellow arc) 230° F to 248° F
Maximum (red line) 248° F

Couple of questions, what is your static RPM at wide open throttle? What is the distance between the muffler and the oil cooler? Many of us have moved the oil cooler forward about an inch to get it away from the muffler (may not be an option for your S-LSA). Is the oil cooler properly seated? Is anything blocking the front or rear of the oil cooler? Have you called Van's?

Your temperatures are way TOO high! Did you mean to say 266 degF??
 
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There is no real published break-in procedure. The high temp is a concern. This can be caused by low fluid level, reduced hose radius (common) when it gets warm that slows flow, a large section of air in the system or an over pitched prop. If you are using Evans coolant this will cause the over heat. Use 50/50. If you are using 50/50 coolant don't go over 248F.
Think of this engine as a motorcycle engine and not a loose tolerance, air cooled Cont. or Lycoming eng. When you buy a new motorcycle you get on it at the sales center and ride it home. If you buy an ATV you take it out a ride it. It was run at the factory for a short time. Let it warm up well for the first flight. During the first flight vary the throttle some. Make sure you don't have the prop pitch set too course so it won't over stress the engine components. Take off rpm can vary some, but right around 4850-5000 is pretty normal. This should give you at least 5500-5650 WOT flat & level rpm.

Check fluids and looks for leaks after landing for the first flight.

Make sure you register your engine with Rotax and make sure you do the 25 hr. Rotax warranty inspection which includes an oil change. Make sure it gets logged in your logbook.

Most of all have fun with your new plane. :D
 
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Rotax 912 ULS break in and oil temp

Thanks to Marty and Roger for their info. Re the oil temp: I had that wrong...the max is up into the caution range at about 235 while cruising at 5000 RPM at about 4500 feet on a warm day. It cools down when I reduce power to 4000....down to about 190. Sorry for the bad dope.

My Max RPM on the bird is about 5200 RPM. I have a total of 23 hours on the engine and bird from Van's. That is how it was delivered.

Re the Rotax Warranty oil change and inspection: I will have local A&P do the oil change and log it but I don't know what the inspection may include...I find no notes on that in any of the Rotax or RV12 docs I have....I think I have all of them.

There are not Rotax certified mechanics in San Diego and I am not aware of any of them anywhere close.

What do you suggest about that?

Thanks a bunch for your advice and help.
EBB:)
 
Ex Bonanza Bucko said:
There are not Rotax certified mechanics in San Diego and I am not aware of any of them anywhere close.

What do you suggest about that?

Thanks a bunch for your advice and help.
EBB:)
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Check with a flight school that offers training on LSAs, they would work with Rotax certified mechanics. I doubt there is no Rotax expertise in the San Diego area.
 
Bruce,
If you are saying that the maximum RPM at wide open throttle while cruising is 5200, then that is too slow. The prop pitch needs to be changed ASAP.
Joe Gores
 
EBB,
There is a Rotax shop at French Valley, only a few minutes flight from you. Let me know if you need more info.
 
Hi EBB,

There are several Rotax mechanics around the San Diego area.

You should cruise above 5000 rpm. (5100-5300 is pretty good) It can run at 5500 rpm its entire life. The engine was never designed to run in the 4000's for extended cruising. A little slow flight scenic viewing is fine, but shouldn't be for the life of the engine.
The higher temps are coming from an over loaded engine from a prop pitch set too course at 5200 rpm at WOT. Flatten that pitch by about 1.75 - 2 degrees and get it up around 5550-5700 rpm in flat and level WOT. 5600-5650 is a good place to be for a ground adjustable prop. Too course a prop pitch cause high temps and engine over stress. Some engines have developed cracks on top of the crank case from this. Getting the rpm up to a more normal range will give you cooler temps, less engine stress, better climb, better cruise and top end and better fuel economy.

Read this and it will help:

http://www.rotax-owner.com/rotax-blog/item/9-understanding-the-ground-adjustable-prop

See these sites for help:

http://rotaxirmt.com/

http://www.rainbowaviation.com/repairman.htm
 
roger lee said:
Hi EBB,

There are several Rotax mechanics around the San Diego area.

You should cruise above 5000 rpm. (5100-5300 is pretty good) It can run at 5500 rpm its entire life. The engine was never designed to run in the 4000's for extended cruising. A little slow flight scenic viewing is fine, but shouldn't be for the life of the engine.
The higher temps are coming from an over loaded engine from a prop pitch set too course at 5200 rpm at WOT. Flatten that pitch by about 1.75 - 2 degrees and get it up around 5550-5700 rpm in flat and level WOT. 5600-5650 is a good place to be for a ground adjustable prop. Too course a prop pitch cause high temps and engine over stress. Some engines have developed cracks on top of the crank case from this. Getting the rpm up to a more normal range will give you cooler temps, less engine stress, better climb, better cruise and top end and better fuel economy.

Read this and it will help:

http://www.rotax-owner.com/rotax-blog/item/9-understanding-the-ground-adjustable-prop

See these sites for help:

http://rotaxirmt.com/

http://www.rainbowaviation.com/repairman.htm
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Roger....and everyone else too: Thanks a bunch for your info. I only have two hours of solo in the bird and after a five hour initial checkout. I suspect that my memory of the rpm at cruise is a little warped because I was intent on learning a whole bunch of new stuff. The ferry pilot who brought the bird here to San Diego from Aurora, Jose Gutierrez, thinks he was turning about 5500 at cruise. I will fly the bird either tomorrow or Friday to confirm that.
I have 23 hours on the airplane now including the ferry time. I have arranged to have a local Rotax mechanic help me/show me and do the oil change and engine inspection needed by the warranty.
If there is a problem with the RPM I will tell you ...and Gus Funnell too but I don't think there is a problem.
Thanks again...and I'll tell you more as I turn myself into an RV12 pilot instead of an old Bonanza pilot :)
 
Ex Bonanza Bucko said:
There are not Rotax certified mechanics in San Diego and I am not aware of any of them anywhere close.

EBB:)
Click to expand...

It looks like you might have found a Rotax qualified mechanic, but just in case:

At Ramona, KRNM, there is a maintenance shop called AeroMechanix. Their manager and lead mechanic is Rotax qualified, and I see Rotaxes in his shop routinely. I'm comfortable recommending them.

http://www.aeromechanix.com/
 
Oil for Rotax 912 ULS

I just took delivery of a new production RV-12 with the Rotax 912 ULS and realized I don't know a anything about this engine. I will be reading the manual but in the meantime can anyone help me locate the type and a source for engine oil. I am located at KBVS, Burlington, WA North of Seattle.
 
Shell makes Aeroshell Sport Plus 4 oil that is designed for the Rotax. You can get it a CPS, Lockwood, Aircraft Spruce etc. The oil is made to help counteract the effects of 100LL in the reduction gear etc. But Rotax suggests that you change your oil every 25 hours or so if you use 100LL.

Up in the Northwest I think you guys are lucky that you have Cargas in 92 octane with no ethanol in it....even on some airports. That's the stuff to burn if you can get it.

Ethanol loves water and the refineries use that to increase the octane rating to 91 (hi test here in Goofafornia). But if you let the gas sit for long and if it's wet outside the ethanol will go to the water and leave the gas with less octane than it used to have......detonation etc.

There probably are others on this Blog with strong opinions about this and you undoubtedly will hear about that. :)
EBB
 
Phil Lockwood Rotax videos

There are several youtube available videos of presentations about Rotax engines that Phil Lockwood has made. You might even get them on the EAA website. He does a really nice job of explaining the reasons behind many of the differences between how you treat a Rotax 912 engine vs. Lycoming or others. Taking the two day service course is valuable, but probably not necessary for everyone. Videos are definitely worth watching.

Congratulations on your new RV!
 
Thank you for the suggestion on the oil and on the cargas which I found both are available in Arlington, WA (KAWO) Arlington Flight Services.
 
Thank you for the advise Brent. I am looking forward to getting more hours on my RV-12. How long have you been flying yours?
 
MVPILOT said:
Thank you for the advise Brent. I am looking forward to getting more hours on my RV-12. How long have you been flying yours?
Click to expand...

First flight was Jan 2014 - I have 147 hours on the hobbs now (clearly I've been spending a lot of time with her). Finally got into the paint shop last week so I'm grounded right now - missing some mid summer 90+ degree weather flying. Its a light airplane and not as enjoyable in breezy weather but that was expected. Has met all my expectations. Maintaining the Rotax is not difficult as long as you closely follow the manuals. I'm, sure you'll be thrilled with yours.

The announcement by Dynon today about 2020 ADS-B compliance with Skyview has been the only outstanding issue I was tracking. Looks like we'll have many years of flying ahead of us. Good luck.
 
I definitely recommend the ROTAX service course, and if you have the time do the Maintenance course. The Maintenance course is probably overkill, but you will definitely know your engine after taking both. I took mine through California Power Systems, and Lockwood also offers them.

Rich
 
Thank you Brent and Rich for the suggestions. I'm sure you are right and I'm going to look forward to learning more about the engine.
 
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