Stihl FS 70 User Manual

FS 70 RC
English
30
If engine is down on power, difficult to
start or runs poorly at idling speed, first
check the spark plug.
Fit a new spark plug after approx. 100
operating hours or earlier if the
electrodes are badly eroded.
Wrong fuel mix (too much engine oil in
the gasoline), a dirty air filter and
unfavorable running conditions (mostly
at part throttle etc.) affect the condition
of the spark plug. These factors cause
deposits to form on the insulator nose
which may result in trouble in operation.
Removing the Spark Plug
N Shut off the engine.
There are two versions:
– Ignition lead on clutch side.
– Ignition lead on starter side.
N Remove the spark plug boot (1).
N Unscrew the spark plug (2).
Checking the Spark Plug
N Clean dirty spark plug.
N Check electrode gap (A) and
readjust if necessary – see
"Specifications".
N Use only resistor type spark plugs of
the approved range.
Rectify problems which have caused
fouling of spark plug:
– Too much oil in fuel mix.
– Dirty air filter.
– Unfavorable running conditions,
e.g. operating at part load.
WARNING
To reduce the risk of fire and burn injury,
use only spark plugs authorized by
STIHL. Always press spark plug boot (1)
snugly onto spark plug terminal (2) of the
proper size. (Note: If terminal has
detachable SAE adapter nut, it must be
attached.) A loose connection between
spark plug boot and ignition wire
connector in the boot may create arcing
that could ignite combustible fumes and
cause a fire.
Installing the spark plug
N Screw home the spark plug, fit the
boot and press it down firmly.
Spark Plug
2
0414BA015 KN
1
2
0141BA020 KN
1
000BA039 KN
A
2
1
002BA363 KN

Stihl FS 70 Specifications

General

Engine Displacement	27.2 cc
Engine Type	2-stroke
Shaft Type	Straight
Fuel Capacity	0.34 l
Engine Power	1.2 bhp
Overall Length	1.7 m
Starter System	Recoil
Power Output	0.9 kW