Mooney M20TN, Service And Maintenance Manual

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MOONEY AVIATION COMPANY, INC.
M20TN SERVICE & MAINTENANCE MANUAL
Date
2006
Rev Date
Page 5
61--00--00 -- GENERAL
The Hartzell propeller is a constant speed, non--coun-
terweighted propeller. Centrifugal twisting moment act-
ing on the blades moves the blades to a low blade angle
(low pitch) to increase RPM. Centrifugal twisting mo-
ment is only present when the propeller is rotating. A
mechanical spring is installed within the propeller to as-
sist movement of the blades to a lower pitch position as
RPM declines, and to reduce the propeller pitch to the
low pitch stop when the propeller is static. Oil pressure
opposes the spring and centrifugal twisting moment to
move the blades to a high blade angle (high pitch), re-
ducing engine RPM. If oil pressure is lost at any time,
the propeller will move to low pitch. This occurs be-
cause the spring and blade centrifugal twisting moment
are no longer opposed by hydraulic oil pressure. The
propeller will then reduce blade pitch to the low pitch
stop.
Hartzell three blade propellers are to be overhauled at
2400 hours. Refer to Hartzell Propeller Owner’s Manu-
al 115N (provided with each propeller) for mainte-
nance, inspection procedures and time intervals.
-- CAUTION --
Refer to Hartzell Service Letter 61 ( ) for most
current overhaul Time--Between--Overhaul limits.
NOTE:
Approved propeller shops ONLY are authorized
for overhaul or major repairs to these propellers.
Refer to Federal Aviation Regulations, Part 43,
(FAR 43) and Federal Aviation Agency Advisory
Circular No. 43.13 ( ) (AC 43.13( ) for definition
of major or minor repairs or alternations and who
may accomplish them.
[(*) = current issue]
DOME UNIT (REF)
SPINNER ASSY
ONE ”THIN” WASHER
TWO ”THICK” WASHERS
(TYP 6 PLCS)
BOLT
(TYP 6 PLCS)
FIBER WASHER (REF)
SCREW (REF)
(TYP 15 PLCS)
WASHER
NUT
(TYP 6 PLCS)
PROPELLER ASSY
BULKHEAD UNIT (REF)
ONE ”THICK” WASHER
NUT
(TYP 6 PLCS)
ENGINE (REF)
SPINNER
INTERNAL SUPPORT
UHMW TAPE
(AS REQUIRED)
HARTZELL “F” FLANGE PROPELLER AND SPINNER DOME
FIGURE 61--1
61--00--10 -- SPINNER DOME AND PROPELLER
REMOVAL
SPINNER REMOVAL
-- CAUTION --
Wrap the blade shanks in several layers of mask-
ing or duct tape before removing the spinner
dome to prevent damaging the blade and blade
paint.
1. Remove the screws and washers that secure the
spinner to the spinner bulkhead (Refer to FIGURE
61--1).
2. Remove the spinner dome.
PROPELLER REMOVAL
NOTE:
If the propeller is equipped with an anti--ice or a
de--ice system, follow the manufacturer’s instruc-
tions for removing the components necessary for
propeller removal.
1. Cut and remove the safety wire (if installed) on the
propeller mounting studs.
AUGUST 2010
61--00--00