![background image](http://html1.mh-extra.com/html/stihl/sp-451/sp-451_instruction-manual_1379763015.webp)
SP 451, SP 481
English
13
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 the engine to run for a
short while at idle speed so that engine
heat can be dissipated by the flow of
cooling air. This protects engine-
mounted components (ignition,
carburetor) from thermal overload.
After Finishing Work
Storing for a short period: Wait for the
engine to cool down. Empty the fuel tank
and keep the machine in a dry place,
well away from sources of ignition, until
you need it again. For longer out-of-
service perionds – see "Storing the
Machine".
Using a harness
STIHL recommends you use the
harness supplied with the machine
because it is specifically designed to
match the machine and the application,
and ensure ergonomic operation.
Putting on the harness and attaching
it to the machine
N
Put your left arm through the
opening in the harness (1).
N
Place the harness (1) on your left
shoulder.
–
The carabiner (2) is on the left side
of your body.
–
The carrying loop (3) is on the left
side of your body.
N
Squat down on the left-hand side of
the machine to save your back
when lifting the machine.
N
Attach the carabiner (2) to the rear
carrying ring (4).
N
Engage the loop (3) in the front hook
(5) by pulling the loop firmly over the
locking bar (6).
Operating Instructions
Fitting the Harness
4902BA016 KN
2
3
4902BA017 KN
4
b
4902BA018 KN
c
a
2
6
5
4902BA019 KN
3