Rotax has released a Mandatory Service Bulletin for 912 / 914 series engines
covering the replacement of the washer part number 944072 on the flywheel hub.
This bulletin affects 912 and 914 engines with specific Serial Numbers.
The serial number ranges of the affected engines are listed in the bulletin.
Due to a deviation in the hardening process, certain washers may have excessive hardness.
This deviation could cause the washer to crack and could cause loosening of the flywheel,
ignition failure or engine damage.
Note that washers part number 944072 delivered as spare parts are not affected.
The bulletin covers specific inspection and replacement instructions for full compliance.