70 - 2
Dismantling and Assembly
- Loader Lift Ram
This procedure applies to Hose Burst Protection Valves
fitted to the loader arm rams ONLY.
The numerical sequence shown on the illustration is
intended as a guide to dismantling.
For assembly the sequence should be reversed.
Dismantling
If possible, avoid disturbing pressure settings, remove
cartridges by unscrewing hexagons
1
and
13
and do not
remove capnuts
3
and
16
.
Spool
2
and check valve
11
each have a Teflon ring fitted
(items
A
and
B
respectively). These Teflon rings should only
be removed and replaced with new ones if they are
damaged.
Do not try to dismantle items
20
,
21
and
22
(these items are
shown for pictorial reference only). To clean, use a non-
metallic probe to move the ball
21
against spring
22
whilst
assembly
17
is submersed in cleaning fluid.
Check condition of all visible seating faces. If any are
damaged, renew complete cartridge or valve assembly.
Check valve bores and spools for nicks, scratches or
scoring, if necessary, renew complete cartridge or valve
assembly.
Assembly
DO NOT apply JCB Threadlocker and Sealer or any other
type of locking fluid to the threads of item
17
. The threads
form an integral part of the valve operating sequences -
applying locking fluid to the threads will seriously effect the
operation of the valve.
Ensure that the small drilled holes
C
and
D
in items
2
and
17
respectively are not blocked.
Renew all seals. If fitting new Teflon rings
A
&
B
, use a
conical guide, such as item
E
, to expand the rings gradually.
Complete the ring fitting procedure as quickly as possible,
otherwise the ring will stretch. See below.
Note:
There is an O-ring
F
fitted underneath each Teflon
ring, if the Teflon rings are to be renewed, make sure that
new O-rings are fitted first.
After assembly, make sure that the valve parts move freely,
if they don't, check that all the seals are correctly fitted.
After refitting the valve to the machine, ensure that pressure
settings are correct, see
Technical Data
page, and check
that the valve operates correctly.
If the pressure settings were disturbed, then the valve must
be re-set, refer to
Service Procedures, Hose Burst
Protection Valves, Pressure Testing - Loader Lift Ram
.
Section E
9803/3280
Section E
70 - 2
Issue 1
Hose Burst Protection Valves
11
F
B
E
A183490
325780