Rotax 912 ULS Ignition Coil Bracket Failure

[Rfisher30]

I'm having a perennial failure of the the ignition coil bracket (Part 851481, #29 below) and am looking to know if anyone else is experiencing the same issue. I've reported the issue to Rotax. Is this a common problem with the part. The brackets seems to fail about every 9-12 months when I find them cracked/broken.

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[avidflyer]

That is a somewhat common occurrence. Although probably not as often as you are having the issue. Wonder if you need to do a better job of syncing the carbs. It would seem that you have a lot of vibration going on. Many have mounted their ignition modules on the firewall side of the motor mount and that takes away the engine vibrations on the modules and wires. I've done that with both of my Kitfox 4s. JImChuk

[DesertFox4]

I did just replace that same bracket on my 912 uls. 🙁
Carbs are balanced nicely and prop is smooth. I ordered a spare bracket just in case it happens again.
I had 450 hours on the original bracket. Looked at relocating ignition modules to firewall side of the engine mount however it looked like I would need to extend all the spark plug wire lengths so decided to try a new bracket for now. By the way, the bracket broke just above where it bolts into the top of the engine.

[3kdscf]

Very interesting. The way I found this post was that I was googling to try and find ANYONE who had this part in stock because none of my regular Rotax sources had it. Yes, I too had this bracket fail and exactly the same way which is right where it bends to attach to the engine block. My first thought when I saw the broken part was "No wonder, the bracket is not nearly wide enough given that large mounting bolt hole."

What I decided to to was fabricate my own bracket from 1" wide stainless steel of the same thickness as the original bracket. I will watch the bracket carefully but I suspect the additional width will prevent it from ever breaking again.

My engine info:
912ULS SN 6785083
Engine Version: 912 ULS2-01
Model Number: 309120110

You can see where my original bracket (left) broke. On the right is my new, wider stainless steel bracket.

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I'm having a perennial failure of the the ignition coil bracket (Part 851481, #29 below) and am looking to know if anyone else is experiencing the same issue. I've reported the issue to Rotax. Is this a common problem with the part. The brackets seems to fail about every 9-12 months when I find them cracked/broken.