Eagle ICA-D212-725, Instructions Manual

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ICA-D212-725 (29)
Page 36 of 50
CHAPTER 29 – HYDRAULIC SYSTEM (29-00-00)

COPYRIGHT

2007 BY DART AEROSPACE LTD.

THIS DOCUMENT IS PRIVATE AND CONFIDENTIAL AND IS SUPPLIED ON THE EXPRESS CONDITION THAT IT IS NOT TO BE USED FOR ANY PURPOSE OR COPIED OR COMMUNICATED TO ANY
OTHER PERSON WITHOUT WRITTEN PERMISSION FROM DART AEROSPACE LTD.
Revision:
6
Date: 13.08.26
29.3.8 Collective Hydraulic Cylinder
A dual hydraulic cylinder, located in left aft pylon
area is used to assist collective control of main
rotor and reduce feed back forces. The hydraulic
cylinder lower valve assembly receives pressure
from two, and system one supplies pressure to
upper valve assembly.
NOTE
When overhaul of hydraulic servo cylinder
assemblies is required, contact Product Support
Engineering, for nearest approved service facility.
29.3.8.1 Removal
29.3.8.1.1 Remove access panel on left side of
pylon island.
29.3.8.1.2 Disconnect hydraulic pressure and
return hoses by removing banjo fittings. Cap or
plug openings. Label hoses for reference at
installation.
29.3.8.1.3 Detach lower end of spring (14, Figure
29-7) and disconnect control tube (16) from input
lever (15). If cylinder is to be replaced, retain
spring (14) for use in reinstallation.
29.3.8.1.4 Remove bolt to disconnect lower end
of cylinder from support (20).
29.3.8.1.5 Remove four nuts and washers to
detach bearing housing (9) from support (10).
NOTE
If transmission is installed, cylinder assembly will
have to be removed by rotating bearing housing
(9) so it will pass down through support (10). If
transmission is not installed, cylinder assembly
can be removed up through support (10).
29.3.8.1.6 Disconnect control tube (5) from
collective lever (1) and remove cylinder assembly.
29.3.8.1.7 Remove boot (6) and detach clevis (8)
from universal (7). Remove clevis with jamnut and
lock.
29.3.8.2 Repair
MATERIALS REQUIRED
NUMBER NOMENCLATURE
C-405 Lockwire
29.3.8.2.1 For
replacement of seals in servo
and bypass valves, refer to Flight Control
Cylinder Overhaul Manual, H.R. Textron, Inc.,
Valencia, California 91355.
29.3.8.2.2
Replace rod end bearings as
follows:
NOTE
Rod end bearing wear tolerance is 0.006 in.
(0.152 mm) radial and 0.012 in (0.305 mm)
axial. Replace bearing if limits are exceeded.
29.3.8.2.2.1 Remove cotter pin, nut, washer
and bolt from rod end bearing (19, Figure 29-7).
29.3.8.2.2.2 Remove lockwire, loosen jamnut
(18) sufficiently to allow rod end to turn. Count
number of turns to remove rod end bearing (19).
29.3.8.2.2.3 Install new KBNE-6W or NHHE6-
21W rod end bearing with same number of
turns.
NOTE
Center line of input lever (15) to center line of
rod end bearing (19) is 16.75 in. (425.45 mm).
29.3.8.2.2.4 With valve body pushed full up
and lower piston pulled full down, adjust lower
rod end bearing (19) to align in support (20).
29.3.8.2.2.5 Install bolt temporarily through
support and rod end. Torque jamnut (18) on rod
end 200 to 250 in-Lbs. (22.60 to 28.25 Nm) and
secure with lockwire (C-405).