SaMASZ FP 20, Operator'S Manual, Page: 16 / 24

Operator's manual
TREE STUMP GRINDER
FP 20
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3.10 Malfunctions and their repair
Table 4. Defects, causes and their repair
No. Defect Reason Repair
1. Tree stump
grinder is not
grinding Damaged or blunt cutting knives Turn the knife by 1/3 turn (special
relieves on the knives), handle for
recovery or replace
Too low PTO rpm Switch rpm to 1000 rpm, increase
engine
’
s rotary speed.
Worn, damaged hydraulic engine Recover hydraulic engine or replace
Damaged or torn bolts securing
hydraulic engine
Replace
Not tight hydraulics Seal or tighten connectors
Improperly adjusted or damaged oil
distributor
Adjust or replace
Cutting disk rotating in opposite
direction
Swap connections
Not tight hydraulic assembly, broken
or torn hydraulic hoses
Remove any non-tightness, replace hoses
2. Tree stump not
evenly ground Damaged or blunt cutting knives Turn knives by 1/3 turn, handle for
recovery or replace
Jerky, non-accurate motions of
extension arm
Improperly adjusted choke valves on
extension arm's cylinders
3. Low rpm of
cutting disk Improper tractor's PTO rpm engaged Switch tractor's PTO shaft rate to 1000
rpm
Low rpm
at tractor's PTO
Increase tractor's engine rotary speed
Worn hydraulic engine Replace
Not tight hydraulics Seal
4. Loud operation
Loose mounting bolts of hydraulic
engine or tree stump grinder
’
s
mounting plate
Tighten bolts
5. Significant
vibrations of the
grinder and the
extension arm Loose cutting knives or knife holders Tighten bolts
Loosened bolt connections Tighten bolts
Cutting knife or knife holder missing Mount cutting knife or knife holder
6. Oil leak Improperly bolted connecting
nozzles
Bolt connecting nozzles
Worn, damaged sealants, fittings Replace sealants, fittings
Not tight hydraulic cylinder Recover
Replace
Any works related to replacement of worn or damaged parts should be done only after the
machine has been switched off, and having previously learned the contents herein. After the engine
has been turned off and the ignition key removed, the vehicle should be secured against any
accidental movement.
Set the machine in a standstill position according to the instructions herein. When conducting
repair works or replacing worn or damaged parts wear protective gloves, protective footwear as
well as protective clothing without any loose elements. When operating with the machine lifted up,
protect it properly with supports and when replacing parts with sharp edges, use personal protective
equipment and corresponding tools. Once works related to replacement of defective parts are
completed, mount back all elements of guards and safety devices.