Some 582UL Engines Built With Mismatched Crankcase Halves

Rotax released a mandatory service bulletin for its 582 UL engines, stating that a limited number were assembled with non-matching crankcase halves. For continued operation, inspection is needed to ensure the correct installation of the crankcase. 

Released in 1989, the 582 UL is a two stroke, 2-cylinder, liquid-cooled aircraft engine designed for ultralight aircraft. If the name rings unfamiliar, it should come as no surprise that production has ended in 2021, as announced by Rotax earlier this year. Much like other light vehicle powerplants, the engine has seen waning popularity in the face of cleaner-burning, less high-strung 4-stroke engines as technology improved. Rotax has sold around 30,000 units throughout its lifespan, and expects its current remaining stock to be sufficient to keep those in service operational for at least 1 year. 

Affected engines vary, but the common issue is the lack of crankcase halves not matched for optimum mating during initial manufacture. Prior to the next flight, owners should inspect the crankcase in accordance with the Rotax Service Bulletin SB-2ST-005. The operation is thankfully a somewhat minor one, simply accessing a position to read the codes below the manifolds to ensure the codes are matching. 

FMI: www.rotax.com