Honda UMK425E Owner's Manual page 10

SHARPENING
CUTTING MEANS (3-TOOTH AND 4-TOOTH)
Sharpening is essential to obtain good results.
A slightly blunt cutting attachment can be sharpened with a file.
A grinding wheel should be used if the wear is more severe.
CAUTION:
• In all cases, the cutting attachment must be kept correctly balanced.
If you do not have the required tools or if you think your cutting
attachment may not be properly balanced, contact your authorized
Honda dealer.
Remove the cutting attachment for sharpening and check that it is not
cracked, out of true or bent.
If it is, replace it with a new one.
Both sides of cutting means (3-tooth and 4-tooth) can be used.
When one side is worn, the cutting attachment should be turned over
to use the cutting edges on the other side.
Only the bevelled edges of the teeth are to be sharpened.
It is important to keep their profile regular and to avoid incipient
fractures.
All the teeth must be sharpened in the same way.
NOTE : If the machine vibrates abnormally after sharpening, this
indicates that the cutting means is unbalanced. In this case, contact
your servicing dealer.
CAUTION:
• Replace the cutting means when the wear limit shown in the
illustrations below has been reached.
[A] Unsatisfactory
[1] Incipient fracture
[2] Limit exceeded and tooth profile
irregular
[3] Angles incorrect and unequal
[4] Unsatisfactory cutting profile
[B] Satisfactory
[5] Sharpening limit
CIRCULAR SAW BLADE
A circular saw blade can be
sharpened using a file [6] if it is only
slightly worn. It is very important to
keep the correct tooth profile, as well
as cutting angles and tooth pitch [3].
If a more extensive sharpening is
required, contact your servicing
dealer who has access to suitable
specialist sharpening equipment.
10 EN
C13
D2 D3
SAFETY
[2]
[1]
[A]
[3]
[4]
30 mm
[5]
[B]
30°
30°
30° 30°
[3]
[6]
1 mm
1 mm
ADJUSTING THE CARBURETOR
PROCEDURE
Start the engine and let it warm up to normal operating temperature.
Then turn the idle screw [7] to the right or left to obtain the correct
setting.
Idle speed
NOTE : When the engine is idling, the cutting attachment must not
rotate.
CHECKING THE SPARK PLUG
1. To reach the spark plug [8],
the top cover must be
removed from the
engine [9]. Use the
hexagonal wrench supplied
to undo the bolt [10].
NOTE : Hot parts and moving parts (flywheel) are exposed when the
engine top cover is removed. Never use your brushcutter with the
engine cover removed.
2. Remove the cap and unscrew the spark plug using the wrench
supplied.
3. Clean the electrodes with a wire brush [11] to remove carbon
deposits.
4. If the electrodes show signs of wear, replace the spark plug with a
new one with the same characteristics.
5. Check the spark plug gap with
feeler gauges [12]. When
adjustment is required, carefully
bend the side electrode.
6. Reinstall the spark plug and
screw it finger-tight onto its seat.
7. For new spark plugs, tighten by
an additional 1/2 turn with the
spark plug wrench. When the
same spark plus is installed, 1/8
to 1/4 of a turn is enough.
TORQUE: 11.8 N∙m (1.2 kgf∙m)
CAUTION:
• If a spark plug is insufficiently tightened, it is liable to heat up and
damage the engine. If the spark plug is overtightened or
crossthreaded, irreparable damage could be caused to the engine
block.
[7]
UMK425E UMK435E
3 100 ± 200 min (rpm)
-1
B7 C1
SAFETY
[8] [9]
[10]
0.6-0.7 mm
[12]
[11]