Dolmar MH-246.4 DS, Original Instruction Manual

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Before performing any maintenance work on the pole hedge trimmer (blade -
cleaning, etc.), always stop the engine and wait until the engine has cooled down.
As an additional safety precaution, also remove the spark plug cap.
Do not try to straighten or weld bent or broken cutting blades. Always replace -
damaged blades.
Stop the engine at regular intervals to check the cutting blades for possible -
damage (perform a tapping-resonance test to detect hard-to-see hairline cracks).
Always make sure that the teeth of the blades are sharp.
Clean the pole hedge trimmer regularly. During cleaning also check all screws, -
nuts and bolts are well tightened.
To reduce the risk of fire, never service or store the pole hedge trimmer in the -
vicinity of open fires.
Always wear rugged protective gloves when handling the cutting blades. -
Contact your dealer for replacement cutting blades. -
Never use gasoline, benzine, thinner, alcohol or the like for cleaning. -
Discoloration, deformation or cracks may result.
Sharpening the blade
If the cutting blades have become blunt and cutting performance is poor, have the
blades sharpened by an authorized service agent.
Adjusting blade clearance
The upper/lower blades wear. If you cannot get a clean cut though the blades are sharp enough, adjust the clearance as follows.
The tightness of the truss bolt decides the clearance of the blades. The nut holds the truss bolt with certain tightness. Too loose clearance
causes blunt cut, but too tight clearance causes unnecessary heat and sooner worn-out of the blades.
1. Loosen the nut (1) with a box or open-ended wrench.
2. Tighten the truss bolt (2) with a hex wrench lightly till it stops. And then, screw it back between a quarter turn and a half turn to gain
necessary clearance.
3. Tighten the nut (1), holding the truss bolt (2).
4. Apply light oil on the friction surface of the blades.
5. Start the engine, operate the throttle on and off for a minute.
6. Stop the engine and touch the surface. If they are not too hot to touch, you have made a proper adjustment. If they are too hot to touch, turn
the truss bolt (2) back a little and repeat the step 5 to 6.
NOTE: Before making the adjustment, stop the engine and wait for the blades to stop.
The blades have a slot around the truss bolt (2). In case you find dust in the end of any of the slots, clean it.
1
2
3
4
5
6
1 Hexagonal U-nut
2 Truss bolt
3 Flat washer
4 Blade guide
5 Upper blade
6 Lower blade
MAINTENANCE