Today Rotax released a new set of new Service Bulletins for the type 9 series engines. The issue found was a hardness problem with the crankshaft protection washer under the bolt and locking washer holding the flywheel in place. Given that Rotax wishes to ensure no problems will be seen in the flied they have decided to replace all washers that were in that lot of materials. This then is only applicable to a serial range of engines and will not affect older engines or any newer ones after that serial range.
4 bulletins were released, 2 for the certified engines, the type 912S series and the 914F series. 2 additional bulletins were released for the 912UL series and the 914UL series. Technicians doing the replacements will want to make sure they refer to the correct bulletin, to attain the serial range that is to receive the SB modification. New parts are already being distributed and many of the engines affected were still in the inventories of the Rotax Aircraft Engines distributors.
Owners and Rotax iRMT ( independent Rotax Maintenance Technicians), are reminded to check the engine log books and verify if the engine has already complied to the bulletin, as a large number were done at the distributor level prior to supply to the OEM and customers. If the part change must be done on an engine in the field the log book must have an entry to indicate that the serial involved has been done in compliance with the bulletin.
The Rotax network of distributors and independent Service Centres will have details of any warranty coverage, should replacement of the washer be needed. Contact your service provider if you have questions or do not understand the bulletin.