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© 2010 Bakker Hydraulic Products B.V.
Nijverheidsweg 6
6662 NG Elst (Gld) The Netherlands
Tel : + 31 481 374757 Fax : + 31 481 375280
3. MAINTENANCE AND REPAIR
-
Check the weld-on hooks visually once a year, and test them once every 4 years
with an 8000 kg load divided into 4000 kg per hook.
-
Test the non-return valve once a year to ensure that it is working properly.
-
Check pins and bushes every year for slack (maximum 0.8 mm).
-
Regularly grease the pivots (steady link, cylinder suspension and pins) to prevent
penetration of sand, dirt, etc.
- After 20 working hours, check all bolted connections and tighten if
necessary.
Caution!
With all maintenance activities on the grab bucket, the grab bucket must be non-
operational and stationed on the ground.
4. TROUBLESHOOTING
Problem:
Load is no longer held.
Possible causes:
- Non-return valve and/or seals
- Piston seals worn
Tips for tracing faults:
-
The cylinder may not display any external leakages. If it does, check that the head
bush is tight. If the head bush is loose, it has to be secured using Loctite type 243
or a similar product.
- With the grab bucket in the open position, disconnect the hoses from the crane
and check whether the grab bucket automatically closes when freely suspended.
If it does:
- The non-return valve and/or seals are/is defective
- Check the piston seals and replace if necessary.
