Hartzell HC-E3YR-7 Owner's Manual page 212

Propeller Owner's Manual
136
(3) An underspeed during the maximum power static
condition may be caused by any one or a combination of
the following: The propeller low pitch blade angle is too
high; the governor is improperly adjusted; the engine is
not producing rated power.
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61-00-36
MAINTENANCE PRACTICES
Rev. 2 Feb/17