Mandatory inspection and/or replacement of the crankcase and/or gearbox housing for ROTAX® engine types 912 iS, 915 iS, and 916 iS fuel-injected engines.

Timothy,

We understand that Service Bulletins can be confusing and overwhelming, so we created a video highlighting the important information in each SB.

https://www.rotax-owner.com/en/videos-topmenu/912-is-videos/804

Rotax has also made significant improvements to make it easier to find the engine S/N, which is now located in the appendix of the certified SB. This makes it very simple to check if your engine S/N is affected.

Any idea what caused the issue? Was is a change in supplier or process?

Based on the information we received, the issue originates from the painting/coating process. After the engine crankcase and gearbox are manufactured to meet specific hardness requirements, they are sent to an external company outside of BRP Rotax for the application of a black paint/coating.

During this application process, the components were placed in a high-heat oven that was operating outside the specified temperature parameters. This deviation potentially affected the hardness of the crankcase and gearbox, an issue identified during BRP Rotax’s quality control hardness testing.

Once Rotax determined that some crankcases and gearboxes might not meet the specified hardness standards, they traced the root cause of the problem and issued this Service Bulletin (SB) as a precaution. Importantly, Rotax has NOT identified any safety risks to the engines related to this issue. They have conducted, and continue to perform, rigorous testing, which is one of the main reasons they request a copy of test results from all affected engines in the field.

At this time, the SB has been released solely as a precautionary measure......" This deviation could possibly lead to reduced endurance of components and/or potential oil leakage"

My engine serial number is 7706xxx, when did they change to 10000xxxx? Is it based on build location or manufacturing year?

Hi Justin

This occurred several years ago.  They ran out of serial blocks and changed from 7 digit numbers to 8.  All aircraft engines are made in Austria so the location is always the same.  Serials are consecutive and not by year.   

Cheers