Echo 73413S Owners Manual v.2 - Handbuch (Seite 13)

10
Service and
Maintenance
Warning: Before inspecting or servicing any
part of the machine, shut off the engine (disen-
gage PTO), and make sure all moving parts have come
to a complete stop. The chipping blades are sharp! Use
care when working on machine to avoid injury.
Check the engine oil, and change the oil and filter as
recommended in the manual. Service and replace the air
cleaner as recommended.
3.1 Sharpening Chipper Blades
The chipper blades will eventually become dull, making
chipping difficult. It is recommended that the chipper
blades are sharpened every 5-15 hours of chipper
operation. To remove the chipping blades for
sharpening:
1. Remove the one 3/8 inch retaining bolt holding
access cover to main frame assembly.
2. Tilt access cover over to allow rotor access. Rotate
the rotor so that the bolts holding a chipping blade
are most accessible.
3. Remove the two hex head bolts holding the blade
itself. Repeat for all four blades. The four chipping
blades have two edges per blade and can be re-
versed one time each before sharpening. If both
sides have not been used, remove and reverse the
chipping blades. Reinstall chipping blades and
proceed with chipping.
To grind the angled edge of the chipping blade to 45
degrees (see figure 5.5, pg. 17):
Grind the blades on a slow-speed wet grinder if
possible, or have them sharpened by a professional. If
you use a bench grinder, be careful when grinding so
that the blade material does not get too hot and change
color–this will remove the blade's special heat treated
properties.
Use short grinding times and cool with water. Try to
remove an equal amount off each blade to maintain
balance.
S
E C T I O N
3
Replace the chipping blades and tighten bolts to 20 ft. lbs.
Close cover and replace bolts.
Note: Never grind on the back side of the chipper blade.
3.2 Chipping Blade Sharpening Tips
Poor chipping performance is usually a result of dull
chipping blades. If your chipper's performance has
decreased, check for the following symptoms:
• Severe vibration when feeding material into the
chipper.
• Small diameter branches do not self-feed.
• Chips discharge unevenly or have stringy tails–
especially when chipping green branches.
Before you sharpen the chipping blades, check for
permanent damage. Replace the blade if:
• The blade is cracked (especially around the bolt
holes) or the edges are too deeply chipped to be
ground smooth.
• The base of the cutting edge is worn or has been re-
sharpened so that it is too close to the rotor chip-
ping slot.
3.3 Setting Chipping Blade Clearance
Blades are sharp; avoid contact with chipper blade
edges.
The four chipping blades should clear the chipper anvil
located directly under the chipper chute by 1/16 inch to
1/8 inch. The chipper anvil is adjustable and reversible.
To adjust:
1. Lift rotor access cover and expose rotor. Loosen the
two 1/2 inch bolts that hold the chipper anvil to the
frame (see figure 5.6, pg. 17).
2. Measure the amount of clearance between chipping
blade and chipper anvil from inside of housing.
3. Adjust inward or outward to desired measurement
using the nuts on the adjustment bolt.
4. Tighten bolts on chipping block to 75 ft. lbs. and
resume operation.
If chipper anvil edge is damaged or worn unevenly,
remove the two bolts holding the anvil and use one of
the other three edges. Adjust for correct measurement.