jcb Mini CX - Page 317

Section E - Hydraulics
Rams
Typical Ram
E-147 E-147
9803-9340-8
Note: The following procedure applies to all rams except
the slew rams.
Dismantling
Place the ram assembly on a locally manufactured strip/
rebuild bench.
Slacken the end cap 1 using a special spanner
K Service
Tools ( T 1-15) and remove the piston rod assembly from
the cylinder.
!M
WARNING
If air or hydraulic pressure is used to force out the
piston assembly, ensure that the end cap is securely
fitted. Severe injury can be caused by a suddenly
released piston rod.
HYD-1-2
Position the piston rod assembly on the bench in place of
the ram cylinder. Remove the piston head seals 2, 3 and 4.
Extract dowel 5 from the piston head using a metric screw
(M3) threaded into the extractor hole.
Note: Any attempt to remove the piston head without
removing the dowel will cause damage to both the piston
head and rod.
Remove piston head 6 from rod 7 using a special spanner
K Service Tools ( T 1-15). Remove the piston head
internal 'O' ring 8.
Remove the end cap 1 from the piston rod and remove the
inner and outer seals 9, 10 and 11.
Bearing 12 may be removed if necessary by drifting out of
the end cap.
Ensure that all metal components are free from scoring,
nicks and burrs. A damaged rod will impair the life of the
inner rod and wiper seals.
Discard all seals and 'O' rings.
Assembling
Thoroughly clean the threads of piston head 6, piston rod
7, end cap 1 and cylinder with a wire brush. Use new seals
and 'O' rings throughout K JCB Ram Sealing
Procedure ( T E-149). Ensure that all threads are free
from grease, hydraulic oil and old locking fluids using JCB
Cleaner/Degreaser. Allow solvent to dry for 15 minutes
before applying JCB Activator.
Ensure that lubricants used during assembly do not come
into contact with the locking fluids.
Apply JCB Activator to the threads of the piston head 6.
Allow to dry for 15 minutes before bringing into contact with
JCB Threadlocker.
Note: Threadlocker and Activator must not contact seals,
bearing rings or 'O' rings.
Apply JCB Threadlocker & Sealer (High Strength) to all
threads of the piston rod. Fit and torque-tighten the piston
head.
Fit the locking dowel 5 to the piston head/rod as follows:
New rod and piston head
If both are required, the following procedure should be
followed:
1 Drill through the piston head into the piston rod,
shown
K Fig 3. ( T E-147). Use an undersized
diameter drill first as a guide and then drill using the
correct size diameter drill to suit: K Table 1. Drilling
Details For Piston Head Retention (all dimensions
in mm) ( T E-148).
Fig 3.
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