Dawson EMV-220 METRIC, Operator'S Instructions/Spare Parts List

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several times – any binding or hesitancy with its operation should result
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anchorage point should be in good order showing no signs of damage,
wear or cracking.
Remember if in doubt change it – Chains, Chain Clamps & Couplers
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f. Inspect the condition of the Hard Jaws. To be acceptable these should
look to be in almost as new condition. The teeth on these pads have
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certainly during extraction. Besides causing a reduction in performance
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Hard Jaw Wear Limit - 90% of all teeth on any hard jaw should
make contactwith the pile and 80% of all teeth should have
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Changing the Hard Jaws – Static Sid e
Remove the Cap Screw that hold this jaw in place. Tap out the old jaw and clean/
inspect the clamp body seating area to ensure the faces are in good order. Slide
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down. Fit the Cap Screw and tighten using a hexagonal wrench. Remember to
install the washers on these screws.
Changing the Hard Jaws – Moving (Cylinder) Side
Release the 8off Cap Screws that hold the Clamp Cylinder in place and remove
the Clamp Cylinder. Undo the two clamp supply hoses, carefully marking them
to ensure correct re-assembly. Once removed, unscrew the round Hard Jaw
counter-clockwise and replace with a new one using a new O-ring. Ensure the
Jaw is fully tightened on the Clamp Cylinder piston rod so that the O-ring
is no
longer visible. Inspect the bronze Guide Bush inside the Clamp Body whilst the
cylinder is out – check the grooves in the front area of the bush and the condition
of the bore. Replace the bush if badly worn.
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functions correctly after completing the work.
g. Inspect the rubber Sandwich Mounts (Elastomers) for wear or damage.
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adjacent to the bonded steel plates and is usually a result of fatigue in
the material over a long period of time. Crazing/softening may occur but
this is usually associated with long term exposure to sunlight or exposure
to petroleum based products. As a general rule change the Sandwich
Mount if any single tare or split exceeds 40mm (1½”) or if the rubber has
become contaminated.
h. Check the overall condition of the Swivel Assembly. Check that the Lifting
Bolt and Nut (that are the centre piece of this assembly) only allow
rotational movement with minimal axial movement. Excessive axial