6
free) and a quality proven motor oil for air cooled 2 cycle
engines.
Recommended mixing ratios:
Models MCS25, MCS38, MCS46, MCS52 and YR4503
Engine Condition
Gasoline to Oil
Up to 20 hours use
25:1
All Models
After 20 hours use
25:1 or 40:1
(see below charts)
When using a mineral oil:
Mixing Ratio 25:1
Gasoline (litres) 1
2
3
4
5
2cycle oil (ml) 40
80
120
160
200
When using a semi-synthetic oil:
Mixing Ratio 40:1
Gasoline (litres) 1
2
3
4
5
2cycle oil (ml) 25
50
75
100
125
WARNING!
Keep open flames away from the area where fuel is handled
or stored. Mix and store fuel only in an approved gasoline
container.
IMPORTANT!
Most engine troubles are caused, directly or
indirectly, by the fuel used on the machine. Take special care
not to mix a motor oil for 4 cycle engines.
HOW TO MIX FUEL
WARNING!
Thorough mixing of the oil and fuel is critical to the
life and performance of the engine. Take extreme
care.
1. Measure out the quantities of gasoline and oil to be mixed.
2. Put some of the gasoline into a clean, fuel container.
3. Pour in all of the oil and agitate well.
4. Pour in the rest of gasoline and agitate again for at least
one minute. Some oils may take longer to mix depend-
ing on their ingredients. Thorough mixing is essential for
engine longevity.
FILLING THE FUEL TANK
1. Untwist and remove the fuel cap. Rest the fuel cap in a
dust free place.
2. Fill fuel tank to 80% of the full capacity.
MSC25 = 184mL, MSC38 = 264mL, MCS46, 52 & YR4503 =
440ml.
3. Fasten the fuel cap securely and wipe up any fuel spillage
from around the engine.
CHAIN OIL
All models
Use Masport Chain Bar Oil Part # 833043. This is specially
formulated to give best results. Alternatively you can use a
good quality motor oil, SAE 10W ~ 30 all year round or SAE
#30~#40 in Summer and SAE #20 in Winter.
Refer to specifications pg13 for OIL TANK capacities.
IMPORTANT!
Do not use waste or recycled oil that can cause
damage to the oil pump.
Open the box and assemble the guide bar and the saw chain
on the power unit as follows:
Note:
For 45, 46 & 52 models assemble spike first. Spike is
not needed for models S25 & 38.
WARNING!
The saw chain has very sharp edges. Use thick
protective gloves for safety.
1. Pull the front guard towards
the front handle to check
that the chain brake is not
engaged.
2. Loosen the nuts and
remove the chain cover.
3. Attach the spike to the
front, saw side of the
power unit.
4. Fix the hanger on the rear of
the power unit by screw - MSC25 only.
YR4503, MCS46 and
MCS52 only- fitting
the Spike
5. Fit the chain over the sprocket and, while feeding the saw
chain around the guide bar, mount the guide bar to the
power unit. Adjust the position of chain tensioner nut on
the chain cover to the lower hole of guide bar.
IMPORTANT!
Pay attention to the correct direction of the saw chain.
6. Fit the chain cover to the power unit and fasten the nuts
until finger tight.
7. While holding up the tip of the bar, adjust the chain tension
by turning the tensioner screw until
the tie straps just touch the bottom
side of the guide bar.
8. Tighten the nuts securely with
the bar tip held up (12–15 Nm).
Then check the chain for smooth
rotation and proper tension while
moving it by hand. If necessary,
readjust.
IMPORTANT!
A new chain will stretch at the beginning of use. Check and
readjust the tension frequently as a loose chain can easily
derail or cause rapid chain wear and damage to the guide bar.
Fuel and Chain Oil Specifications
WARNING!
Gasoline is very flammable. Avoid smoking
or bringing any naked flame or sparks near
the fuel.
Make sure to stop the engine and allow it to
cool before refuelling the unit. Select outdoor
bare ground for fuelling and move at
least 3m (10ft) away from the fuelling point before starting the
engine.
Mix a regular 91 octane gasoline (leaded or unleaded, alcohol
Hole
Tensioner
nut
Chain cover
Tensioner screw
MCS38
MCS25,
45,46, 52
