27Series 4144 Powerhead
– Inspect the piston ring and
replace if necessary, b 6.7.1
– Install the cylinder, b 6.4
– Remove the engine – see service
manual for "Series 4144
Components – FS, FC, KM"
– Tightening torques, b 3.3
– Reassemble all other parts in the
reverse sequence.
6.7.1 Piston Ring
– Remove the piston, b 6.7
– Remove the piston ring from the
piston.
: Use a piece of old piston ring to
scrape the groove (arrows)
clean.
938RA072 TG938RA073 TG
: Position the new piston ring in the
groove so that the radii (arrows)
at the ring gap face upwards.
: Position the piston ring so that
the radii at the ring gap meet at
the fixing pin in the piston groove
(arrow).
– Check correct installed position
of the piston ring.
– Install the piston, b 6.7
938RA074 TG938RA075 TG
7. Ignition System
Exercise extreme caution when
troubleshooting and carrying out
maintenance or repair work on the
ignition system. The high voltages
which occur can cause serious or
fatal accidents.
Troubleshooting on the ignition
system should always begin at the
spark plug, b 4.2
– Remove the shroud – see service
manual for "Series 4144
Components – FS, FC, KM"
The electronic (breakerless) ignition
system basically consists of an
ignition module (2) and flywheel (1).
2
938RA076 TG
1