Partner 351 Chainsaw Manual

The Partner 351 is a professional-grade chainsaw designed for demanding forestry and arborist work. It features a powerful 2-stroke engine, automatic chain oiling, anti-vibration system, safety chain brake, and ergonomic design for extended use. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

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

Feature	Description
Engine Type	2-stroke, air-cooled gasoline engine
Displacement	51.7 cc
Power Output	3.2 kW (4.3 hp)
Guide Bar Length	15-20 inches (standard)
Chain Pitch	3/8" or .325"
Automatic Oiling	Adjustable chain lubrication system
Safety Features	Chain brake, throttle lockout, right-hand guard
Anti-Vibration	Spring-mounted handles for reduced fatigue
Weight (dry)	Approx. 6.2 kg (13.7 lbs)
Fuel Capacity	0.55 liters

Safety Information

Read all instructions before use. Wear appropriate PPE.

1. Personal Protective Equipment: Always wear safety glasses, hearing protection, gloves, chainsaw chaps, and steel-toe boots.
2. Work Area Safety: Clear area of bystanders, especially children. Ensure secure footing.
3. Kickback Prevention: Hold saw firmly with both hands. Do not cut with tip of bar. Maintain chain sharpness and tension.
4. Fuel Safety: Refuel in well-ventilated area with engine off and cool. Use approved fuel mix.

WARNING! Chainsaw kickback can cause severe injury or death. Always engage chain brake when not cutting.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach Guide Bar: Remove side cover. Place bar over studs, ensuring oil hole aligns.
2. Install Chain: Fit chain over bar sprocket, ensuring cutting teeth face forward on top.
3. Tension Chain: Adjust tensioning screw until chain snaps back when pulled from bar.
4. Fill Fluids: Add 2-stroke fuel mix (50:1 ratio) to fuel tank. Fill bar/chain oil tank.

CAUTION! Ensure chain is correctly installed and tensioned before starting. Loose chain can derail.

Specifications

• Engine: 2-stroke, single cylinder, 51.7 cc.
• Fuel: Unleaded gasoline (min 90 octane) mixed with 2-stroke oil (50:1).
• Idle Speed: 2,800 RPM.
• Maximum Power Speed: 9,500 RPM.
• Sound Pressure Level: 112 dB(A).
• Vibration Level: Front handle 5.2 m/s², rear handle 4.8 m/s².
• Ignition System: Electronic, capacitor discharge.
• Carburetor: Walbro or equivalent, adjustable H and L jets.
• Warranty: 2 years commercial, 5 years private use (subject to registration).

Controls and Components

Main controls located on top and rear handle.

Front Handle: Chain brake lever, throttle trigger lockout, hand guard.

Top Panel: Choke control, primer bulb, stop switch, decompression valve (if equipped).

Rear Handle: Throttle trigger, master control lever (combines choke/run/stop).

Left Side: Side cover tensioning screw, oil filler cap.

Right Side: Fuel filler cap, air filter cover.

Starting Procedure

Cold Start: Place saw on flat ground. Engage chain brake.

1. Press decompression valve (if equipped).
2. Set master control lever to choke (full up).
3. Press primer bulb 5-6 times until fuel is visible.
4. Pull starter cord sharply until engine fires (1-3 pulls).
5. Move lever to half-throttle position. Pull again to start.
6. Allow to warm up at idle for 30 seconds before disengaging brake.

Warm Start: Set lever to run position (middle). Pull starter cord.

Operation Guidelines

Basic cutting techniques for felling, limbing, and bucking.

1. Felling: Plan escape path. Make notch cut (1/3 diameter), then back cut. Use wedges if needed.
2. Limbing: Stand uphill. Support saw with thigh. Cut from top down, keeping bar clear of ground.
3. Bucking: Support log. Cut from top, avoid pinching bar. Use plastic or wooden wedges.
4. Kickback Zone: Avoid contact with upper quadrant of bar tip.

Tip: Let chain do the work; do not force saw. Maintain steady throttle in cut.

Maintenance Schedule

Daily (before use): Check chain tension, sharpness, and lubrication. Inspect for loose parts.

Weekly: Clean air filter, check spark plug, clean cooling fins, inspect bar for wear.

Monthly: Clean fuel filter, check carburetor adjustment, inspect anti-vibration mounts.

Annually: Replace fuel lines, clean exhaust screen, check clutch and sprocket.

Chain & Bar Care

Keep chain sharp and properly tensioned. Rotate bar regularly.

1. Sharpening: Use round file (4.5mm for 3/8" chain). Maintain 30° top plate angle. File all cutters evenly.
2. Tensioning: Chain should be snug against bar but pull freely. Re-tension when warm.
3. Bar Maintenance: Clean bar groove weekly. Flip bar monthly for even wear. Dress rails with flat file if burred.
4. Oiling: Ensure oiler is working. Adjust flow rate for conditions (higher in dirty/dry wood).

CAUTION! Always wear gloves when handling chain. Disconnect spark plug wire.

Storage Instructions

For storage over 30 days, prepare saw to prevent fuel system damage.

1. Drain fuel tank and run engine until it stops.
2. Remove spark plug, add 1 tsp of 2-stroke oil through spark plug hole. Pull starter 2-3 times to coat cylinder.
3. Clean entire saw, especially cooling fins and air filter.
4. Remove chain, clean and soak in oil. Store bar flat.
5. Store in dry, cool place, covered to prevent dust.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, flooded, fuel issue	Check spark plug, dry plug if wet, ensure fuel mix is fresh.
Engine runs then dies	Clogged fuel filter, vent	Replace fuel filter, clean tank vent.
Poor power/acceleration	Dirty air filter, carb adjustment	Clean/replace air filter, adjust H/L jets.
Chain doesn't oil	Empty oil tank, clogged port	Fill tank, clean oil holes in bar, check oil pump.
Chain comes off bar	Loose chain, worn sprocket	Tension chain properly, replace drive sprocket if worn.
Excessive vibration	Loose parts, worn mounts	Tighten all bolts, replace anti-vibration springs.

Service: For technical support, contact authorized Partner service center. Use genuine Partner parts.

Parts & Support: www.partnerpower.com or call 1-800-555-PARTNER