Stihl MS 661 C-M Instruction Manual

Stihl MS 661 C-M manual cover
Pages 148
Year 2020
Language(s)
English en
Spanish sp

Stihl MS 661 C-M Specification

The Stihl MS 661 C-M is a professional-grade chainsaw designed for demanding forestry and logging applications, delivering exceptional power and performance. It features a robust 91.1 cc engine, producing a power output of 5.4 kW, enabling efficient handling of large timber. The saw incorporates Stihl's M-Tronic™ engine management system, which automatically adjusts the fuel mixture and optimizes performance based on environmental conditions, ensuring consistent power and easy starting.

This model is equipped with an advanced anti-vibration system, reducing operator fatigue during extended use by minimizing vibration levels. The ergonomic design includes a comfortable handle arrangement, enhancing user control and precision. With a weight of approximately 7.4 kg (without cutting equipment), the MS 661 C-M balances power with maneuverability.

The chainsaw is fitted with a high-capacity air filtration system, featuring a long-life air filter for extended maintenance intervals, contributing to its durability and reliability. The Ematic™ chain lubrication system ensures optimal lubrication with reduced oil consumption, supporting efficient operation and prolonging chain life.

Safety features include a quick-stop chain brake and a throttle lockout lever, providing enhanced protection for the user. The side-access chain tensioner simplifies chain adjustments, promoting ease of maintenance. Available with various bar lengths, the MS 661 C-M offers versatility for different cutting tasks.

Designed for professional use, the Stihl MS 661 C-M combines cutting-edge technology with robust construction, making it a preferred choice for forestry professionals who require a powerful, reliable, and efficient tool.

Stihl MS 661 C-M F.A.Q.

How do I start the Stihl MS 661 C-M chainsaw?

To start the Stihl MS 661 C-M, ensure the chain brake is engaged, move the Master Control Lever to the cold start position, pull the starter rope until the engine fires briefly, then move the lever to the warm start position and pull the rope again until the engine starts.

What is the recommended maintenance schedule for the Stihl MS 661 C-M?

Regular maintenance for the Stihl MS 661 C-M includes cleaning the air filter after every 5 hours of use, sharpening the chain as needed, checking the chain tension before each use, and inspecting the spark plug every 100 hours.

Why won't my Stihl MS 661 C-M start?

If your Stihl MS 661 C-M won't start, check the fuel level, inspect the spark plug for damage or fouling, ensure the air filter is clean, and verify that the stop switch is not engaged.

How do I properly adjust the chain tension on the Stihl MS 661 C-M?

To adjust the chain tension, loosen the nuts on the sprocket cover slightly, turn the tensioning screw clockwise to increase tension or counterclockwise to decrease it, and ensure the chain fits snugly against the bar while still allowing it to be pulled manually. Tighten the nuts to secure the cover.

What type of fuel mix is required for the Stihl MS 661 C-M?

The Stihl MS 661 C-M requires a 50:1 ratio of gasoline to two-stroke engine oil. Use high-quality, unleaded gasoline with a minimum octane rating of 89 and Stihl's branded two-stroke oil for optimal performance.

How can I troubleshoot an overheating issue with my Stihl MS 661 C-M?

To troubleshoot overheating, ensure the air filter and cooling fins are clean, verify the fuel mixture is correct, and check for any exhaust blockages. Operating the chainsaw with a dull chain can also cause overheating.

What are the steps to replace the chain on the Stihl MS 661 C-M?

To replace the chain, remove the sprocket cover by loosening the nuts, take off the old chain, place the new chain on the guide bar ensuring the teeth face forward, fit the chain around the sprocket, and adjust the tension before securing the cover back in place.

How do I clean the air filter on the Stihl MS 661 C-M?

To clean the air filter, remove the top cover, take out the filter, and gently clean it with warm soapy water or use compressed air to blow out dirt. Ensure the filter is completely dry before reinstalling it.

Why is my Stihl MS 661 C-M losing power during operation?

If your Stihl MS 661 C-M is losing power, check the air filter and spark arrestor for blockages, inspect the fuel filter for clogs, and ensure the carburetor is properly adjusted. Additionally, verify that the chain is sharp.

What safety precautions should I take when using the Stihl MS 661 C-M?

When using the Stihl MS 661 C-M, always wear appropriate personal protective equipment including gloves, ear protection, and safety glasses. Ensure the chain brake is engaged during startup, be aware of your surroundings, and follow all operational guidelines in the user manual.