Chainsaw Operation and Safety Procedures

Saw Operation and Warm-Up

• Begin by allowing the saw to idle on a pad or soft ground while monitoring its behavior.
• During warm-up, hold the saw with both hands and gradually rev it to full RPM two to three times.
• Verify proper operation of the chain brake before cutting.
• Check chain and bar oiling: rev the saw and observe for oil droplets on a light-colored surface.
• To shut off the saw, switch the master control to "stop" after idling.
• Restart a hot engine in the "run" position without choking if necessary; maintain master switch in "stop" when idle.
• Always engage the chain brake before moving a running saw.

Chain Brake Usage

• Engage the chain brake by pushing the black hand-guard towards the nose of the bar.
• Release the brake by pulling the hand-guard toward the hand-grip before cutting.
• The chain brake must be activated when the saw is stored to ensure safety.

Chain Tension Adjustment

• Regularly check and adjust chain tension using the tension-adjusting screw.
• For cold tension, ensure the chain is tight but does not bind; chain tie-straps should touch the bar rails.
• Adjusted warm chain tension should have the tangs halfway up the bar groove; verify tension after cooling for accuracy.

Chain Replacement Procedure

• Loosen bar retaining nuts and back off the bar adjusting screw to remove the chain.
• Ensure carbide teeth on the bar point towards the tip upon reinstalling.
• Adjust slack in the chain by turning the adjusting screw while lifting the bar tip.
• Secure connections by tightening the nuts while maintaining correct chain tension.

Flooded Saw Management

• A flooded saw indicates excess unburned fuel in the combustion chamber, making starting difficult.
• Position the saw in "run" and out of "choke," then have one person stabilize it while another pulls the starter rope with the throttle fully open.

Cut-off Saw Overview

• Circular saws are versatile, capable of cutting various materials with appropriate blades.
• Uses include ventilation, forcible entry, heavy rescue, and vehicle extrication.
• Before cutting, ensure sparks do not ignite flammable surroundings and inspect cutting wheels for defects.

Safety Precautions for Cut-off Saws

• Always operate with a safety guard and check for wheel integrity before use.
• Avoid cutting asbestos materials to mitigate health risks.
• Follow guidelines to prevent kickback, ensuring a high-speed blade is used.

Cutting Wheel Types

• Composite abrasive wheels can cut materials like asphalt and steel but cannot cut railway tracks.
• Diamond abrasive wheels excel in wet cutting for asphalt and concrete; different letters denote wheel types based on application.

Minor Maintenance Practices

• Clean the air filter regularly to prevent dirt from entering the intake area.
• Adjust the V-belt tension by loosening nuts, turning the nut clockwise, and then retightening.
• To change cutting wheels, use a locking pin for safety while loosening hexagon screws.

Inventory and Maintenance Reporting

• District saws are labeled with an Inventory Identification Number for tracking and maintenance.
• Maintenance involves generating a Work Order Ticket and attaching an Out of Service Tag with details of the problem and identification number.

Specifications for Stihl Chainsaws

• Stihl MS391 and MS362:
  • Displacement: 3.9 cu in
  • Engine Power: 3.3 kW
  • Powerhead Weight: 13.67 lbs
  • Fuel Capacity: 20.3 oz
  • Chain Oil Capacity: 11.8 oz