THOR 202 Security Alert
Belleville Spring preload of the centrifugal clutch
During some scheduled control tests on Thor 202 we detected a possible defect in the preload of
the centrifugal clutch Belleville springs in engines with serial number between 929*07038 and
929*07867.
Due to the low preload of the springs inside the clutch weight, the propeller keeps on turning even
at 1800 RPM
Although this defect does not present a safety problem during the flight phases, Belleville springs
must be replaced; if not replaced they could cause the clutch breakage with a consequent much
more invasive maintenance.
For any further information please contact your official Polini dealer who sold you the Thor
engine.
