OPERATING INSTRUCTIONS
Handle bar
Blade release lever
Hood
Rear guide 
Blade block 
Front guide wheel 
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 operate saw if there is a fuel leak!
Insure all guards are secure, undamaged and properly in- stalled.
WARNING
Do not operate the saw unless all guards, safety equipment and the engine kill switch are in place and operational!
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.
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.
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.
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.
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.
WARNING
Do not leave the saw unattended while the engine is running! Always secure the saw from movement while unattended.
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.
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.
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