Operation Manual

19BR 420
English / USA
During break-in period
A factory new machine should not be run
at high revs (full throttle off load) for the
first three tank fillings. This avoids
unnecessary high loads during the
break-in period. As all moving parts
have to bed in during the break-in
period, the frictional resistances in the
engine are greater during this period.
The engine develops its maximum
power after about 5 to 15 tank fillings.
During operation
After a long period of full-throttle
operation, allow engine to run for a while
at idle speed so that the heat in the
engine can be dissipated by flow of
cooling air. This protects engine-
mounted components (ignition,
carburetor) from thermal overload.
After finishing work
Wait for engine to cool down. Drain the
fuel tank. Store the machine in a dry
place. Check tightness of nuts and
screws (not adjusting screws) at regular
intervals and retighten as necessary.
Dirty air filters reduce engine power
increase fuel consumption and make
starting more difficult.
If there is a noticeable loss of engine
power
: Turn choke knob to g
: Release the screws (1) and pull
off the filter cover (2).
: Remove the main filter (3) from the
cover and inspect it –
if it is dirty or damaged, fit a new
one.
: Always install a new prefilter when
you change the main filter.
: Take the prefilter (4) out of the filter
cover.
: If the prefilter is wet, dry it – then
knock it out on the palm of your
hand or blow out with compressed
air.
: Always replace a damaged prefilter.
Operating Instructions Cleaning the Air Filter
1
373BA017 KN
2
1
373BA018 KN
3
4
5