Rotax has issued a mandatory Alert Service Bulletin for certain serial numbers of the certified 912 A, 912 F, 912 iSc Sport, 914 F, plus a similar mandatory Alert Service Bulletin for non-certified model 912 UL, 912 ULS, 912 iS Sport, and 914 UL engines. Dated June 22, 2026, the bulletins address potential issues in the propeller gearbox of the affected engines and require inspection for missing M7x16 hexagon screws (intended to secure the propeller shaft bearing in the propeller gearbox) and oil spray nozzle assembly. The bulletin says, in part, that the missing screws may allow axial displacement of the propeller shaft bearing that could result in a loss of oil and engine shutdown.
(Photo: Larry Anglisano)
The good news is the failure won’t cause the propeller shaft to be pulled out of the gearbox housing. Rotax has listed the serial numbers of the engines requiring inspection inside the bulletins, and compliance is as follows:
- On stored engines and spare parts: prior to their delivery.
- On delivered engines and spare parts: before the initial installation, but at the latest after one year from the date of the initial issue of the Alert Service Bulletin.
- On already installed engines and spare parts (with less than 25 hours of operation): carry out the inspection before the next flight but at the latest after one year from the date of the initial issue of the Alert Service Bulletin.
- On already installed engines and spare parts (with more than 25 hours of operation): carry out the inspection at latest within the next five hours of operation, but at the latest after one year from the date of the initial issue of Alert Service Bulletin.
Rotax is providing a labor credit for work performed by technicians with a current applicable iRMT rating.
“Hey – anyone know why we have all these extra M7x16 hexagon screws on the stock take?” 🙂
Item #24 on the IPC
Thank you, Larry and AvBrief, for this and other coverage of Rotax matters. It’s great that you guys recognize there are quite a few of us out here flying behind Rotax engines.
There’s a lot of Rotax engines in service! Go to Rotax-Owners.com and sign up to recieve bulletins
Thank you, Bill. I’m a long-time subscriber. I agree it’s an absolute must if you own a Rotax. I was just expressing my gratitude to AvBrief for publishing news items related to Rotax engines.
👍…
Any one who flies behind (or in front of) a Rotax engine should look into joining Rotax-Owner.com. I got an email on this SB a day or two ago and always get timely information about the engines.
I second that!
It’s interesting to note that the very same defect is found in both Experimental and Certified versions of the affected engines. Kind of ruins the illusion of Certified having a greater level of scrutiny.
A ROTAX IS A ROTAX!
I think I read that for Rotax, the only difference between the certified and experimental engines is the paperwork.
What does a Rotax turn up before the gear box reduces the prop shaft down?
From memory 5,400RPM take-off and 5,200 continuous.
Thanks.