Upright POWERED ACCESS TL34, Service Manual

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RESTRICTORS
You have seen that all valve blocks
have restrictors fitted at different
locations.The TL34 uses hose Adapters
with a drilled hole.
OUTRIGGER CONTROL VALVE
When the spool is in the neutral position
the annular side of the ram is attached
to the tank line. This is done to ensure
that the pilot pressure holding the check
valve on the full bore open, is drained
off quickly to tank so that the check
valve close quickly
If the valve block is replaced make sure
that the piping is done exactly as
shown. You rely on the closed port as
your back up for the check on the full
bore side.
Some early version did not have this
type of spool. This type can easily be
identified as it has Din-Oil stamped on
the end cap. This type used a standard
closed centre valve block. The leakage
rate across the closed centre spool was
high enough to ensure that the check
would close
Hose adapter shown here with drilled hole.
If cylinder movement is erratic check for
contamination
Each A port has a restrictive hose adapter fitted
in the valve block. If the restrictor gets blocked
you will not be able to operate the cylinder
correctly.
When looking for a fault relating to cylinders and
valve blocks - swapping hose connection can
easily give a good pointer to where the fault is. If
the fault stays put, you know that the fault is in
the valve block. If the fault moves you know it is
the cylinder. Do not over tighten the hose fitting.
You are more likely to cause a leak by deforming
the adapter cone than leaving the fitting to loose.
MAINTENANCE PROCEDURE
JACK CYL. 1
Ø1.4mm
JACK CYL. 2
Ø1.4mm
JACK CYL. 3
Ø1.4mm
JACK CYL. 4
Ø1.4mm
160 BAR
STABILISER VALVE
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