Hartzell HC-B3-2 Series Owner's Manual And Logbook page 205

(c) Grease Leakage - probable causes:
1 Loose/defectice lubrication fitting
2 Grease leaks between the blade clamp and the
propeller hub
a Refer to a certified propeller repair station
with the appropriate rating.
3 Grease leaks past the blade clamp seal gaskets
4 Grease leaks from between the blade clamp and
the blade
a Refer to a certified propeller repair station
with the appropriate rating.
5 Grease leaks from the clamp when the blade is
pointed up and in a static position.
a Oil separating from the grease. Approved
lubricants are listed in the Maintenance
Practices chapter of this manual. These
lubricants have varying separation rates.
1
(d) Oil Leakage - probable causes:
1 Faulty O-ring seal between the hub and the
cylinder
2 Faulty O-ring seal between the piston and the
cylinder
3 Displaced felt seal between the piston and the
cylinder
4 Faulty O-ring(s) between the propeller hub and
the engine flange
5 Faulty O-ring between the piston and the pitch
change rod
(e) Beta Tube/Valve System Oil Leakage (if applicable)
- probable causes:
1 Faulty O-rings between the beta tube/valve.
a Refer to a certified propeller repair station
with the appropriate rating for replacement.
INSPECTION AND CHECK
Propeller Owner's Manual
139
If a clamp seal leaks after the first
ten hours of operation, consult a
certified propeller repair station with the
appropriate rating.
61-00-39
Page 5-19
Rev. 17 Apr/20