Jonsered 2050 Chainsaw Manual

The Jonsered 2050 is a professional-grade chainsaw featuring a 50cc engine, automatic chain oiling, anti-vibration system, inertia-activated chain brake, quick-release air filter, and side-mounted chain tensioner. Designed for demanding forestry and cutting tasks, it offers reliable performance with proper maintenance. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: 50cc 2-stroke engine, 16-20 inch guide bar, automatic oil pump, chain brake, decompression valve, air injection system.

Safety Instructions

Always wear protective gear: helmet, goggles, gloves, chainsaw chaps, and steel-toe boots.

1. Clear work area of obstacles and bystanders.
2. Check chain tension and sharpness before each use.
3. Ensure chain brake is functional.
4. Use proper fueling procedures outdoors.
5. Never operate above shoulder height.

WARNING! Chainsaw kickback can cause severe injury. Maintain firm grip and proper stance.

Assembly & Preparation

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

1. Attach guide bar: Loosen bar nuts, position bar, align chain, tighten nuts.
2. Adjust chain tension: Use side tensioner until chain snaps back when pulled.
3. Fill fuel: Use 50:1 gasoline/oil mix (Jonsered 2-stroke oil recommended).
4. Fill chain oil: Use quality bar & chain oil.
5. Check controls: Ensure throttle trigger, throttle lock, and chain brake work smoothly.

CAUTION! Fuel is flammable. No smoking during fueling. Wipe spills immediately.

Specifications

• Engine: 50cc 2-stroke, air-cooled.
• Power output: 3.2 kW (4.3 hp).
• Fuel capacity: 0.55 L.
• Oil capacity: 0.26 L.
• Idle speed: 2,800 rpm.
• Max power speed: 9,500 rpm.
• Weight (dry): 5.2 kg (without bar & chain).
• Sound level: 112 dB(A) at operator's ear.
• Vibration levels: Front handle 3.2 m/s², rear handle 4.5 m/s².
• Spark plug: Champion RCJ7Y or equivalent.

Controls and Components

Main controls: Front handle with chain brake, rear handle with throttle trigger, throttle lockout, choke, decompression valve, master control lever.

Master control lever: Combines choke, stop switch, and start position.

Chain brake: Manual activation via front hand guard; inertia activation during kickback. Decompression valve: Reduces cylinder pressure for easier starting. Air filter: Quick-release cover for easy cleaning. Chain tensioner: Side-mounted screw for bar adjustment.

Starting & Operation

Cold start procedure:

1. Engage chain brake.
2. Set master control to choke position.
3. Press decompression valve (if equipped).
4. Pull starter cord until engine fires.
5. Move master control to half-throttle position.
6. Pull starter cord again until engine starts.
7. Blip throttle to disengage choke.
8. Release chain brake before cutting.

Tip: Warm start: Use half-throttle position, no choke.

Maintenance Procedures

Daily maintenance checklist:

1. Check chain tension and sharpness.
2. Inspect chain brake function.
3. Clean air filter (tap or wash with soapy water).
4. Check fuel and oil levels.
5. Inspect guide bar for wear and damage.
6. Clean cooling fins and spark arrestor screen.
7. Check all nuts and bolts for tightness.

WARNING! Always disconnect spark plug before performing maintenance.

Chain & Bar Care

Proper chain maintenance ensures performance and safety.

1. Sharpening: Use round file matching chain pitch (typically 3/8").
2. Filing angle: Maintain 30° cutting angle.
3. Depth gauge: File rakers to 0.025" below cutter.
4. Bar maintenance: Clean bar groove weekly; flip bar monthly for even wear.
5. Chain lubrication: Adjust oil flow rate for cutting conditions.

CAUTION! Dull chains increase kickback risk and reduce cutting efficiency.

Storage Guidelines

Long-term storage preparation:

1. Drain fuel tank and run engine until carburetor is empty.
2. Remove chain, clean, and soak in oil.
3. Clean entire saw, especially cooling fins.
4. Remove spark plug, add teaspoon of oil, pull starter slowly.
5. Store in dry, cool place with bar and chain separately.

Tip: Use fuel stabilizer if storing with fuel for less than 30 days.

Warranty Information

Jonsered 2050 includes 2-year consumer warranty for defects in materials/workmanship when used for personal purposes. Commercial use may have different terms. Warranty does not cover normal wear, misuse, improper maintenance, or non-genuine parts. For warranty claims, contact authorized Jonsered dealer with proof of purchase. For support, visit www.jonsered.com or contact customer service.

Troubleshooting

Service: For repairs beyond basic maintenance, contact authorized Jonsered service center.

Support: www.jonsered.com | Customer service hotline available in manual.