Husqvarna 450 - Manual (Page 8)

8
OPERATING INSTRUCTIONS
Experience is very important when running the 450 saw. A
skilled worker is highly recommended. Always do an inspec-
tion of the saw before starting the engine. Open the hood
(H) and check the fuel (D) and oil level (A) per the enclosed
engine manual. SAE 10W/30 oil and unleaded gasoline with
an 87 or higher octane should be used. Observe all safety
regulations for the safe handling of fuel. Always check the
engine oil with the saw turned off, completely lowered and
the engine level! Check that all controls are in good working
order. Check for loose bolts or nuts. Check for fuel or oil leaks.
WARNING
Do not leave the saw unattended while the engine
is running! Always secure the saw from movement
while unattended.
Insure all guards are secure, undamaged and properly in-
stalled.
To start the engine, turn the fuel valve (C) on by the carburetor
on the side of the engine. Raise the saw by pushing down on
the handle bar (Q) with both hands to the full locked position.
Push the engine kill switch (I) to the “ON” or “1” position. Push
the engine throttle control (N) 1/3 of the way. Close the engine
choke by pulling the engine choke knob (F). The closed choke
position enriches the fuel mixture for starting a cold engine.
The open choke position provides the correct fuel mixture for
operation after the engine starts and for restarting a warm
engine. Start the engine by pulling the rope handle (L) on the
back of the saw. After the engine starts, slowly open the choke
by pushing the engine choke knob (F). Allow the engine to
warm for a few minutes.
WARNING
Do not operate saw if there is a fuel leak!
WARNING
Do not operate the saw unless all guards, safety
equipment and the engine kill switch are in place and
operational!
Periodically, clean any excess concrete from inside the blade
block, scrappers and blade cover. Always clean the blade
block assembly thoroughly before storing the saw. Always
close fuel valve before transporting. Do not walk on the
joints or transport equipment across the joints until the
concrete fully hardens.
Handle bar
Blade release lever
Blade block
Front guide wheel
Check the air filter (B) and clean or replace if necessary.
Check for proper specification of blade and that the skid plate
operates properly. Check that the blade and skid plate are in
good condition. Check that the handle is in the full upright and
locked position and the handle locking knob (M) is tight. Make
sure the work site is clean, well lit and hazard free.
WARNING
ASPHYXIATION HAZARD
Running an engine in a confined or badly ventilated
area can result in injury or death due to asphyxiation
or carbon monoxide poisoning.
WARNING
Before each use, carefully inspect the 450 for any
damage to any of its parts and components. Pay
careful attention to any leakage of gasoline or oil.
Under no circumstance should the 450 or any of its
attachments be operated if you find damage or are
suspicious that something appears to be damaged.
Open the engine throttle lever (N) to full open position for
maximum engine speed shown on the tachometer (G). Lower
the front guide (J) to the full down position by pushing the front
guide control lever (O) forward.
When approaching a wall, raise the front guide and use the
triangle guide at the back of the blade block and the rear guide
on the wheel (K) to cut the last few feet. Do not hit the blade
block assembly against any object. Damage may result.
Push down on the back of the handle bar to raise the saw out
of the cut to the full and locked position. Move the engine throt-
tle lever to the full closed position. Turn the engine kill switch to
the “OFF” or “0” position.
Line up the saw with the cut line using the front guide wheel,
the rear guide (K) and the triangle pointer on the back of the
blade block. Push down on the saw handle and pull the blade
release lever (P) to lower the blade in the concrete slowly.
Push the saw forward to cut keeping the front guide wheel on
the cut line.
Push the saw at about half speed for the first 50 feet to allow
the blade to develop good diamond exposure or open up and
promote blade life. Increase the forward speed of the saw until
the blade and the engine are working at maximum efficiency.
Do not force the saw.
Rear guide
Hood