Deutscher GARDEN CHIPPER 750, Руководство по эксплуатации и обслуживанию

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MAINTENANCE
Drive belt adjustment / replacement (contd)
• If the belt is in good condition, loosen the nut (1) furthest from the belt on the threaded
rod attached to the clutch lever, using a 13mm open-ended spanner. See sketch below.
• With the clutch lever in the ‘fully down’ position, wind the nut (1) about 2mm away from
the adjacent boss (3), then wind the other nut (2) outwards until both nuts are firmly in
contact with the boss.
• Raise the clutch lever fully and check the belt tension. The far side of the belt should
deflect about 12 mm when pushed firmly inwards. See sketch on page 15.
• If the belt is not yet tight, repeat the process.
• Should you run out of adjustment, the belt will need to be replaced.
• Tighten both nuts against the boss, then replace the plastic belt guard. Do not over-
tighten the belt guard nuts, or you will distort the guard.
• To
replace a belt
, simply lower the clutch lever and wind nut (2) fully inwards. Replace
the belt by winding it onto the two pulleys.
imporTanT:
ENSURE THAT THE BELT IS
INSIDE THE TWO BELT GUIDES THAT ARE ATTACHED TO THE SIDE PLATE OF THE
ENGINE. FAILURE TO CHECK COULD RESULT IN A RUINED BELT.
Chipper blade replacement/ sharpening
The chipper blades will become blunt with extended use, particularly if you are chipping dry
hardwood. You can feel when the blades are blunt, as the processing time is longer and the
engine is more likely to slow down under heavy loading. To sharpen the blades:
• Switch off the engine and remove the spark plug lead from the spark plug.
• Using two 13mm spanners, remove the two 8mm nuts that secure the sloping cover plate
(above the discharge chute) and the M8 bolt and nut that secure the side cover plate
(adjacent to the sloping cover plate). Remove both plates.
• With the clutch lever disengaged, turn the rotor until one chipper blade is opposite the
opening created by removing the covers. Providing the disc is not rotated by hand, you
can re-engage the clutch to hold the disc in position, while removing the blade.
• Using a nail or a similar sharp object, clean the allen key holes in the three countersunk
screws that retain the chipper blade.
• With the 5mm allen key on the outside and a 13mm spanner on the inside, remove the
three screws that secure the chipper blade to the rotor disc.
• Remove and inspect the chipper blade. The sloping edge can be sharpened at 40 degrees
to the top surface using a fine grinding wheel. Remove only a minimum of material,
until you feel that the edge is sharp. Initially the blade is 45mm wide. With repeated
resharpening, the blade will reach 40mm wide. At this time it should be replaced. Turn
the disc and repeat the removal and sharpening operation for the second blade. Try and
keep both blades the same width to ensure the rotor stays in balance.
• Before refitting the chipper blades, clean the surface of the disc behind the blades and
ensure that the blades sit flat on the sloping machined surface. Replace the retaining
screws if they appear worn or damaged. Always use new 8mm nyloc nuts and tighten
them securely. Do noT USE PLAIN 8MM NUTS. THE CHIPPER BLADE COULD FLY OUT
OF THE CHAMBER OR SMASH INTO THE ANVIL IF THE BOLTS BECOME LOOSE.
• Once the blades are securely bolted, rotate the rotor disc slowly by hand, and check that
both chipper blades do not hit the anvil that is at the base of the hopper.
• Replace the maintenance cover plates.