4.4
Cradle jams
Occasionally the cradle may become jammed at some point in the tipping cycle. This is
usually a minor problem which can be easily corrected.
The cradle is not powered down
–
it is lowered by gravity alone.
See
for details and schematics of the hydraulic system.
Cradle jams while raising
There are two types of problem which can prevent the cradle from lifting when the RAISE
button is pressed:
overload
and
mechanical
faults.
4.4.1.1
Overload fault
1.
Lower the cradle to ground level, open the door, and remove the bin.
2.
Manually remove some material from the bin to lighten it, then try again.
If the pressure-relief valve is adjusted incorrectly, the cradle can stall even when lifting
bins that are within the
ch ’
. The pressure-relief
valve may only be adjusted by a qualified technician with authorisation from Simpro.
4.4.1.2
Mechanical fault
1.
If possible, lower the cradle to ground level, open the door and remove the bin.
2.
Attempt to visually identify the cause of the jamming. The most likely problems are:
a.
One of the lifting chains being derailed from the top chain guide
(accessed by removing the cover plates at the top of the mast).
b.
The mast being bent or damaged, jamming one of the mast rollers
c.
Part of one of the curved tipping tracks being bent, interfering with the
correct movement of the follower rollers
d.
Lack of lubrication of the follower rollers or main cradle axle
e.
The cradle being out of level due to poorly adjusted or broken lifting chains.
A technical guide on adjusting the MegaDumper lifting chains is available from Simpro.
f.
The roller arms
pressing too tightly against the tipping tracks, due to
the cradle being either out of level, or not correctly centred in the masts.
3.
With the cradle lowered, rectify the problem by lubricating, straightening and/or
realigning the mechanical components as required. If the mast is bent, you may
need to contact your agent for support.
4.
Close the door and test the machine to see if the cradle now lifts correctly.
5.
Run the machine through several complete tipping cycles to ensure the problem has
been fully resolved.
Cradle jams while lowering
There are three types of problem which can prevent the cradle from lowering when the
LOWER button is pressed:
hydraulic, electrical,
and
mechanical
faults.
4.4.2.1
Hydraulic or electrical fault
When the LOWER button
is pressed, the lowering valve should make
‘cl ck’
sound as it opens. If it does not, the problem is likely to be either a hydraulic or electrical fault.
