CESSNA®
MODEL 550/551
MAINTENANCE MANUAL
SHIMMY DAMPER - SERVICING
1. General
A. This procedure gives the information necessary to complete the servicing of the shimmy damper.
2. Tools and Equipment
A. For a list of tools and equipment, refer to Table 301.
Table 301. Equivalent substitutes can be used for the listed item as follows:
NAME NUMBER MANUFACTURER USE
Hydraulic service CJMD112-002 Cessna Aircraft Co. To fill the shimmy damper.
pump Citation Marketing Division
Department 579
P.O. Box 7706
Wichita, KS 67277
3. Shimmy Damper Servicing
A. Complete the Servicing of the Shimmy Damper. Refer to Figure 301.
NOTE: The measurement probe must be larger than 0.160 inch (4.06 mm) in diameter to prevent
entry into the threaded hole in the make-up piston. A tie-strap about 6.0 inches (152.4
mm) long is acceptable.
(1) Open access plate 211FZ in the nose baggage area to get access to the shimmy damper. Refer
to Chapter 6, Access Plates and Panels Identification - Description and Operation.
(2) Open the nose wheel-well doors. Refer to Chapter 32, Nose Landing Gear and Doors - Removal/
Installation .
(3) Put a probe in the open end of the retainer cap to measure the depth of the make-up piston in
the shimmy damper.
(a) If the measurement is between 4.5 inches (114.3 mm) and 4.6 inches (116.8 mm), the
servicing procedure is complete.
(b) If the measurement is less than 4.5 inches (114.3 mm) or more than 4.6 inches (116.8 mm),
complete the servicing procedure given below.
(4) Remove the service port cap.
NOTE: It helps to make sure that there is no unwanted air in the hydraulic service pump
hose before you connect it to the service port.
NOTE: It helps to use a 90-degree adapter fitting to connect the hydraulic service pump
to the service port.
(5) Use a container to catch the spilled hydraulic fluid.
(6) Connect a hydraulic service pump with Skydrol to the service port. Refer to Chapter 29, Main
Hydraulic System - Maintenance Practices, for safety precautions.
(7) Use the hydraulic service pump to fill the shimmy damper.
NOTE: Fluid can come out of the retainer cap during this procedure.
(8) Loosen the bleed-screw as necessary on the shimmy damper to release unwanted air.
(9) Tighten the bleed-screw on the shimmy damper.
(a) The measurement of the make-up piston must be more than 4.5 inches (114.3 mm) after
you bleed the unwanted air.
(10) Loosen the bleed-screw until the make-up piston measurement is between 4.5 inches (114.3
mm) and 4.6 inches (116.8 mm).
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CESSNA®
MODEL 550/551
MAINTENANCE MANUAL
(11) Disconnect the hydraulic service pump.
(12) Install the service port cap.
(13) Fully flush the retainer cap with alcohol to remove all of the unwanted hydraulic fluid.
(14) Discard the extra hydraulic fluid and clean the container.
(15) Close access plate 211FZ in the nose baggage area. Refer to Chapter 6, Access Plates and
Panels Identification - Description and Operation.
(16) Close the nose wheel-well doors. Refer to Chapter 32, Nose Landing Gear and Doors - Removal/
Installation .
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© TEXTRON AVIATION INC. Aug 1/2008
CESSNA®
MODEL 550/551
MAINTENANCE MANUAL
A4677
SERVICE PORT CAP
A
SERVICE A
PORT
SHIMMY DAMPER
MEASUREMENT PROBE
RETAINER CAP
DETAIL A
BLEED SCREW
VIEW A−A A5542T3023
AA6542T1014
Shimmy Damper Servicing
Figure 301 (Sheet 1)
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© TEXTRON AVIATION INC. Aug 1/2008
