Fuel - Stihl FS 300 Instruction Manual

English
N Block the drive shaft.
N Screw on the nut (4)
counterclockwise and tighten it
down firmly.
Remove the tool used to block the
shaft.
Removing the cutting attachment
N Block the drive shaft.
N Unscrew the mounting nut
clockwise.
If the mounting nut has become
too loose, fit a new one.
18

Fuel

This engine is certified to operate on
unleaded gasoline and with the mix ratio
50:1.
Your engine requires a mixture of high-
quality premium gasoline and high-
quality two-stroke air-cooled engine oil.
Use premium branded unleaded
gasoline with a minimum octane rating
of 89 RON.
Note: Models equipped with a catalytic
converter require unleaded gasoline. A
few tankfuls of leaded gasoline can
reduce the efficiency of the catalytic
converter by more than 50%.
Fuel with a lower octane rating may
result in preignition (causing "pinging")
which is accompanied by an increase in
engine temperature. This, in turn,
increases the risk of the piston seizure
and damage to the engine.
The chemical composition of the fuel is
also important. Some fuel additives not
only detrimentally affect elastomers
(carburetor diaphragms, oil seals, fuel
lines etc.), but magnesium castings as
well. This could cause running problems
or even damage the engine. For this
reason it is essential that you use only
high-quality fuels!
Fuels with different percentages of
ethanol are being offered. Ethanol can
affect the running behaviour of the
engine and increase the risk of lean
seizure.
Use only STIHL two-stroke engine oil or
equivalent high-quality two-stroke air-
cooled engine oils for mixing.
We recommend STIHL 50:1 two-stroke
engine oil since it is specially formulated
for use in STIHL engines.
Do not use BIA or TCW (two-stroke
water cooled) mix oils!
Use only STIHL 50:1 heavy-duty
engine oil or an equivalent quality two-
stroke engine oil for the fuel mix in
models equipped with a catalytic
converter.
Take care when handling gasoline.
Avoid direct contact with the skin and
avoid inhaling fuel vapour.
The canister should be kept tightly
closed in order to avoid any moisture
getting into the mixture.
The fuel tank and the canister in which
fuel mix is stored should be cleaned
from time to time.
Fuel mix ratio
Only mix sufficient fuel for a few days
work, not to exceed 3 months of storage.
Store in approved safety fuel-canisters
only. When mixing, pour oil into the
canister first, and then add gasoline.
Examples
Gasoline Oil (STIHL 50:1 or equiva-
lent high-quality oils)
liters liters
1 0.02
5 0.10
10 0.20
15 0.30
20 0.40
25 0.50
FS 300, FS 350, FS 400, FS 450, FS 480
(ml)
(20)
(100)
(200)
(300)
(400)
(500)