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Thanks, I ordered one from him.
The Rotax 91xis series of engines have 2 generator stators that are incorporated in the body of the engine itself. Engine oil is used as a coolant to cool the generator stators. As generators, any non-used watts has to be dissipated as heat, thus the importance of adequate cooling. Initially the stator cooling was just by passive oil splash, that was proven in adequate and a nozzle was incorporated to be more efficient/effective by spraying oil under pressure directly on the B generator coil. This works well. However, for a number of engines, a build error at the factory used the wrong Loctite sealant and this resulted in a few engines being produced that had clogged or restrict nozzles and subsequent stator failure. The Service Bulletin has owner's test flow through the nozzle to insure adequate oil cooling flow can be maintained. The test tool attaches to the nozzle and a minmimum flow is measured with the flowmeter.
The oil squirter cools the stator on the internal generators in the 912 engines. A number of engines had the squirter nozzle installed with too much Loctite during factory assembly, which could potentially decrease oil flow enough to cause the stator to overheat and self-destruct. Rotax issued an Alert Service Bulletin in December 2024 requiring the oil flow through the nozzle to be measured, and the nozzle replaced if low; this requires the special tool discussed above. If low flow, the nozzle requires replacement.
In addition, certain engines did not have a nozzle (according to Lockwood) and mine is one of them. It cannot be installed by just loosening the engine mount bolts (as for the sb inspection), but the entire engine must be removed. Without the squirter some very expensive damage will occur. Luckily, my engine had not been run before this information came out.
