40
41
Replacing a spark plug
Recommended spark plugs:
BPR6ES (NGK) or W20EPR-U (DENSO)
The recommended spark plugs have the correct thermal
coefficient for normal engine operating temperatures.
Risk of burns!
The engine and adjacent com-
ponents can be very hot after
operation.
Physical contact with the engine
can cause burn injuries to the
skin.
–
–
–
Only perform maintenance
while engine is switched off.
–
–
–
–
Avoid physical contact with the
engine and adjacent compo-
nents shortly after operation.
–
–
–
–
Leave the engine sufficient
time to cool down.
An incorrect or a loose spark
plug can cause damage to the
engine.
Excessive tightening of the spark
plug can damage the thread in
the cylinder head.
To enable the spark plugs to function properly, they must
have the correct electrode spacing and be free of deposited
sediment.
Proceed as follows to replace a spark plug:
1. Remove the spark plug connector and then remove all
dirt from the surrounding area.
2. Unscrew and remove the spark plug using a 13/16 inch
spark plug wrench.
3. Check the exterior of the spark plug. Replace the spark
plug if it is damaged or very dirty, if the sealing disk is in
poor condition and/or if the electrodes are worn.
4. Measure the electrode spacing of the spark plug with
a wire feeler gauge. If necessary, correct the electrode
spacing by carefully bending the side electrode.
–
Side electrode spacing: 0.7 to 0.8 mm
5. Carefully tighten the spark plug by hand to prevent the
thread from getting stripped.
6. Tighten down the spark plug using a 13/16-inch spark
plug wrench to compress the sealing disk.
–
–
–
–
Tighten down a new spark plug once settled into
position by a further 1/2 turn to compress the disk.
–
–
–
After a new spark plug has settled into position,
tighten it a further 1/8 or 1/4 turns to compress
the disk.
Setting the idle speed
1. Start the engine in the open air and run it until it reach-
es operating temperature.
2. Set the throttle lever to its minimum position.
3. Turn the throttle detent screw to maintain nominal idle
speed.
–
Nominal idle speed: 1400 ± 150 rpm
EN
GLISH
DEUT
SC
H
TORQUE WRENCH WT 1400 P
OPERATING MANUAL
Bef
ore
st
ar
ting
wo
rk
Fir
st
mont
h
or 20 hour
s
Ev
er
y
3 mont
hs
or 50 hour
s
Ev
er
y 6
mont
hs
or 100 hour
s
Annuall
y
or e
ver
y
300 hour
s
Ev
er
y
1000
hr
s
Transmission g
rease
Chang
e
×
Engine oil
Chec
k
×
Chang
e
×
×
Air filt
er
Chec
k
×
Clean
×
Chang
e
×
Spar
k plug
Clean / set
×
Chang
e
×
Sediment cup
Clean
×
Idle speed
Chec
k / set
×
V
al
ve clearance
Chec
k / set
×
Combus
tion c
hamber
Clean
×
Fuel t
ank and fuel filt
er
Clean
×
Fuel hoses
Chec
k
×
R
ubber seals
Chec
k t
hat unit
is undamag
ed
×
Fir
m seating of scre
w
s
Validat
e
×
Engine
Chec
k mounting
×
CAUTION
NOTE
NOTE
Table 8:
Maintenance intervals