Morrison Chainsaw Manual

The Morrison Chainsaw is a professional-grade gasoline-powered chainsaw designed for heavy-duty cutting, pruning, and felling tasks. It features a high-performance 2-stroke engine, automatic chain oiling, anti-vibration system, safety chain brake, quick-stop inertia brake, and ergonomic handles for extended use. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: 2-stroke gasoline engine, guide bar, cutting chain, chain brake, throttle trigger, choke control, primer bulb, fuel tank, oil tank, and anti-vibration system.

Feature	Description
Engine Type	2-stroke, air-cooled gasoline engine
Displacement	45cc (varies by model)
Guide Bar Length	16-inch or 18-inch options
Chain Pitch	3/8-inch low-profile
Automatic Oiling	Adjustable chain lubrication system
Safety Features	Chain brake, inertia brake, hand guard
Anti-Vibration	Reduced vibration handles
Weight	Approximately 10.5 lbs (without fuel)
Fuel Mix	Gasoline and 2-stroke oil (50:1 ratio)
Warranty	2-year limited warranty

Safety Instructions

Read all instructions before operation. Wear proper safety gear.

1. Always wear: Safety glasses, hearing protection, gloves, chainsaw chaps, and steel-toe boots.
2. Clear work area of bystanders, especially children and pets.
3. Inspect chainsaw before each use: Check chain tension, sharpness, and all controls.
4. Never operate with one hand or above shoulder height.
5. Be aware of kickback zone (upper quadrant of guide bar tip).

WARNING! Gasoline is flammable; refuel in well-ventilated area with engine off and cool. Do not smoke near fuel.

Assembly & Preparation

Unpack and inspect all parts. Assemble on a clean, flat surface.

1. Attach guide bar and chain: Loosen bar nuts, position bar, loop chain over sprocket, adjust tension.
2. Fill fuel tank: Mix unleaded gasoline (89 octane or higher) with 2-stroke oil at 50:1 ratio.
3. Fill chain oil tank: Use quality bar and chain oil (not motor oil).
4. Check chain tension: Chain should snap back when pulled from guide bar.

CAUTION! Ensure chain is installed with cutting teeth facing forward. Overtightening can damage bar and chain.

Specifications

• Engine: 2-stroke, 45cc displacement.
• Power Output: 2.8 HP at 9,500 RPM.
• Fuel Capacity: 14.9 fl oz (440 ml).
• Oil Capacity: 8.5 fl oz (250 ml).
• Idle Speed: 2,800 RPM.
• Maximum Speed: 13,500 RPM.
• Sound Level: 105 dB(A) at operator's ear.
• Vibration Level: Front handle: 4.5 m/s²; Rear handle: 5.2 m/s².
• Emissions: Meets EPA Phase III and EU Stage II standards.

Controls and Components

Main controls: Throttle trigger, throttle lockout, choke control, primer bulb, stop switch, chain brake lever.

Front Handle: Contains throttle trigger, throttle lockout, and chain brake lever. Rear Handle: Contains stop switch and choke control. Top Cover: Contains air filter, spark plug, and primer bulb.

Chain tensioning: Located near guide bar mount; adjust with combination tool. Oil flow adjustment: Screwdriver slot near oil tank cap (clockwise to decrease, counterclockwise to increase).

Starting & Stopping

Starting procedure (cold engine):

1. Place chainsaw on flat ground, clear of debris.
2. Engage chain brake by pushing lever forward.
3. Move choke lever to FULL CHOKE position.
4. Press primer bulb 5-6 times until fuel is visible.
5. Pull starter rope briskly until engine fires (usually 2-3 pulls).
6. Move choke to HALF CHOKE, pull starter until engine runs.
7. Disengage chain brake before cutting.

Stopping: Release throttle, press stop switch to OFF position.

Operating Procedures

Basic cutting techniques:

1. Felling: Plan escape path (45° behind tree). Make notch cut (1/3 diameter), then felling cut.
2. Limbing: Work from trunk outward. Support limbs when possible.
3. Bucking: Support log off ground. Cut from top down, avoid pinching chain.
4. Pruning: Use bottom of guide bar for control. Beware of springback.

Kickback Prevention: Maintain firm grip, do not cut with tip, keep chain sharp, use reduced-kickback chain.

Maintenance & Cleaning

Daily maintenance checklist:

1. Clean air filter: Remove, tap clean, or wash with soapy water if foam.
2. Check spark plug: Clean electrode, gap at 0.025 inch (0.65 mm).
3. Clean cooling fins and cylinder area.
4. Inspect chain for damage, sharpen if needed.
5. Check all nuts and bolts for tightness.

Weekly: Clean fuel filter, check fuel lines, clean guide bar groove, inspect sprocket.

Chain Sharpening

Tools needed: Round file (5/32" or 4.0 mm), file guide, depth gauge tool.

1. Secure bar in vise or clamp.
2. File each cutter from inside to outside at 30° angle.
3. File all cutters to same length.
4. Check depth gauges; file down if above recommended height.
5. File rakers (depth gauges) to 0.025 inch below cutter.

Tip: Sharpen chain every 1-2 hours of use for optimal performance.

Storage Guidelines

Long-term storage (over 30 days):

1. Drain fuel tank completely or add fuel stabilizer.
2. Run engine until carburetor is dry.
3. Remove chain, clean and soak in oil.
4. Clean entire chainsaw thoroughly.
5. Store in dry, cool place, away from children.

CAUTION! Never store with fuel in tank for extended periods; fuel degrades and damages carburetor.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, fuel issues, flooded	Check spark plug, fuel mix, choke setting; wait if flooded.
Engine runs then dies	Clogged fuel filter, air filter	Clean/replace fuel filter, clean air filter.
Chain doesn't turn	Chain brake engaged, clutch worn	Disengage brake; inspect clutch and sprocket.
Chain throws oil	Over-oiling, wrong oil type	Adjust oil flow; use proper bar and chain oil.
Excessive vibration	Loose parts, unbalanced chain	Tighten all fasteners; sharpen chain evenly.
Poor cutting performance	Dull chain, improper filing	Sharpen chain correctly; check depth gauges.

Service: For repairs beyond basic maintenance, contact authorized Morrison service center at 1-800-555-CHAIR (2424) or visit www.morrisonchainsaw.com/support.