Stihl MS 170 Chainsaw Instruction Manual

1. Product Overview

The Stihl MS 170 is a compact and environmentally friendly petrol chainsaw, featuring a catalytic converter. It is ideally suited for various tasks such as maintaining trees, clearing forests, and cutting firewood. This model is capable of felling trees up to 30 cm (approximately 12 inches) in diameter, offering a balance of power and maneuverability for both professional and home use.

Figure 1.1: Side view of the Stihl MS 170 Chainsaw, showcasing its compact design.

2. Safety Information

Operating a chainsaw requires strict adherence to safety guidelines to prevent injury. Always read and understand the complete safety manual provided with your Stihl MS 170 before operation.

• Personal Protective Equipment (PPE): Always wear appropriate PPE, including a helmet with face and hearing protection, safety glasses, heavy-duty gloves, chainsaw protective trousers or chaps, and safety boots.
• Work Area: Ensure the work area is clear of bystanders, pets, and obstacles. Maintain a safe distance from others.
• Fuel Handling: Handle gasoline and oil with extreme care. Mix fuel in a well-ventilated area away from ignition sources. Do not smoke while refueling.
• Kickback Prevention: Be aware of kickback hazards. Always maintain a firm grip with both hands on the chainsaw handles. Avoid cutting with the tip of the guide bar.
• Chain Brake: Familiarize yourself with the chain brake mechanism and ensure it is always functional.
• Anti-Vibration System: While the chainsaw features an anti-vibration system, prolonged use can still cause fatigue. Take regular breaks.

Figure 2.1: Operator demonstrating safe use of the Stihl MS 170 Chainsaw with appropriate safety equipment.

3. Setup

3.1. Unpacking and Assembly

Carefully remove all components from the packaging. The Stihl MS 170 typically comes with the guide bar and saw chain detached. Follow these steps for assembly:

1. Place the chainsaw on a stable, flat surface.
2. Remove the chain sprocket cover by loosening the two nuts.
3. Fit the saw chain onto the guide bar, ensuring the cutting edges are facing in the correct direction.
4. Place the guide bar onto the studs, then fit the chain around the drive sprocket.
5. Replace the chain sprocket cover and hand-tighten the nuts.
6. Adjust chain tension using the tensioning screw. The chain should be snug but still able to be pulled around the guide bar by hand.
7. Tighten the chain sprocket cover nuts firmly.

3.2. Fuel and Chain Oil

The Stihl MS 170 is a petrol-powered chainsaw and requires a specific fuel mixture and chain lubricant.

• Fuel Mixture: Use a high-quality two-stroke engine oil mixed with unleaded gasoline at the ratio specified in your detailed manual (typically 50:1 for Stihl 2-stroke oil). Always use fresh fuel.
• Chain Lubrication: Fill the chain oil reservoir with high-quality bar and chain oil. The chainsaw features a chain lubrication system that automatically oils the chain during operation. Ensure the reservoir is adequately filled before each use.

Figure 3.1: Top view of the Stihl MS 170 Chainsaw, highlighting the fuel and oil filler caps.

4. Operating Instructions

4.1. Starting the Chainsaw

Follow these steps to start your Stihl MS 170:

1. Place the chainsaw on firm ground.
2. Engage the chain brake.
3. Set the master control lever to the choke position (cold start) or half-throttle (warm start).
4. Press the fuel primer bulb several times until fuel is visible.
5. Pull the starter cord firmly until the engine fires briefly.
6. Move the master control lever to the run position.
7. Pull the starter cord again until the engine starts.
8. Briefly blip the throttle to disengage the half-throttle lock (if applicable).

4.2. Cutting Techniques

Always maintain a stable stance and firm grip. Let the saw do the work; do not force it. The anti-vibration system helps reduce operator fatigue during extended use. The zoom compensator ensures consistent engine performance under varying load conditions.

• Felling: Plan your felling direction. Make a notch cut on the side of the tree facing the felling direction, then make the felling cut from the opposite side.
• Limbing: Remove branches from a felled tree. Work from the base towards the top, cutting smaller branches first.
• Bucking: Cutting a felled tree into logs. Ensure the log is stable and supported to prevent pinching the guide bar.

Figure 4.1: An individual using the Stihl MS 170 Chainsaw to cut logs, demonstrating proper handling.

5. Maintenance

Regular maintenance ensures optimal performance and extends the life of your chainsaw.

• Chain Sharpening: A sharp chain is crucial for efficient and safe cutting. Sharpen the chain regularly or replace it when dull.
• Guide Bar Maintenance: Clean the guide bar groove and oil holes. Flip the guide bar periodically to ensure even wear.
• Air Filter: Clean the air filter regularly to maintain engine performance. Replace if damaged.
• Spark Plug: Inspect and clean the spark plug. Replace if necessary.
• Cooling Fins: Keep the engine's cooling fins clean to prevent overheating.
• Chain Oil Reservoir: Monitor the chain oil level and refill as needed. Ensure the chain lubrication system is functioning correctly.

6. Troubleshooting

7. Specifications

8. Warranty and Support

For detailed warranty information, please refer to the warranty card included with your product or visit the official Stihl website. For technical support, spare parts, or service, please contact your authorized Stihl dealer or Stihl customer service directly. Ensure you have your model number (MS 170) and serial number ready when contacting support.

Stihl products are known for their durability and availability of spare parts. The EU Spare Part Availability Duration is listed as 2 Years, indicating commitment to product longevity.