5 Most Common STIHL MS 170 Problems: Causes and Solutions

When it comes to dependable chainsaws, the STIHL MS 170 is a popular choice among homeowners and professionals alike. Its reputation for reliability and performance has made it a trusted tool for cutting firewood, trimming trees, and tackling various outdoor projects.

However, like any mechanical device, the STIHL MS 170 may encounter issues over time. In this blog post, we’ll provide a comprehensive guide to the 5 most common STIHL MS 170 problems, along with their causes and solutions.

Brief Overview of the STIHL MS 170 Chainsaw

The STIHL MS 170 is a lightweight and compact chainsaw designed for ease of use and maneuverability. It boasts a 30.1cc engine, a 16-inch bar, and a chain capable of making quick work of small to medium-sized cutting tasks. Its ergonomic design and user-friendly features have made it a favorite tool for many who need a reliable chainsaw in their arsenal.

Importance of Understanding Common Problems

Chainsaws, like all machinery, require maintenance and care to perform at their best. Understanding the common problems that may arise with your STIHL MS 170 is essential for several reasons:

  • Preventative Maintenance: Identifying issues early can prevent costly repairs and downtime.
  • Safety: Addressing problems promptly ensures the chainsaw remains safe to operate.
  • Performance: Solving common issues helps maintain the tool’s efficiency and cutting power.
  • Longevity: Proper care and timely repairs can extend the life of your chainsaw.

Purpose of the Blog Post

The primary purpose of this blog post is to empower STIHL MS 170 owners with the knowledge they need to diagnose, troubleshoot, and resolve the most frequently encountered issues. By the end of this article, you will have a comprehensive understanding of the following problems:

  1. Difficulty Starting the STIHL MS 170: We’ll explore the common causes of starting problems, including stale or contaminated fuel and clogged air filters. You’ll also learn how to properly manage fuel and maintain the air filter for smooth starts.
  2. Loss of Cutting Power: If your STIHL MS 170 isn’t cutting like it used to, we’ll examine the causes, such as dull or damaged chains and incorrect chain tension. We’ll guide you through the process of sharpening the chain and ensuring the correct chain tension for optimal performance.
  3. Oil Leaks: Oil leaks can be messy and indicative of underlying issues. We’ll discuss worn or damaged oil caps and problems in the oiler system, along with solutions to address these problems effectively.
  4. Chainsaw Overheating: Overheating can lead to damage and reduced performance. We’ll look at the causes, including dirty cooling fins and improper usage, and provide guidance on cleaning and using your chainsaw responsibly to avoid overheating.
  5. Unwanted Vibrations: If your STIHL MS 170 is vibrating excessively, it can be uncomfortable to use and may indicate problems. We’ll delve into the causes, such as loose components and worn chain sprockets, and explain how to identify and remedy these issues.

By the end of this blog post, you’ll be well-equipped to tackle these common problems and ensure your STIHL MS 170 continues to serve you reliably and efficiently. Let’s dive into the details of each issue and how to address them effectively.

Problem 1: Difficulty Starting the STIHL MS 170


Starting your STIHL MS 170 should be a simple process, but if you find yourself struggling with this, there are a couple of common causes to consider:

  1. Stale or Contaminated Fuel: One of the primary reasons for difficulty starting your STIHL MS 170 is using stale or contaminated fuel. Over time, gasoline can deteriorate, leading to a poor fuel mixture that doesn’t combust effectively. Contaminants in the fuel can clog the carburetor, further complicating the starting process.
  2. Clogged Air Filter: An air filter in your chainsaw prevents dust and debris from entering the engine. If the air filter is clogged with dirt and sawdust, it can restrict the airflow, making it harder for the engine to get the oxygen it needs for combustion.


To address difficulty starting your STIHL MS 170, consider the following solutions:

  1. Proper Fuel Mixture and Storage: Ensure you are using fresh, high-quality gasoline mixed with STIHL’s two-stroke oil in the recommended ratio (typically 50:1). It’s essential to use a clean container for fuel storage and avoid letting fuel sit for extended periods. If your chainsaw has been sitting idle for an extended time, drain the old fuel and replace it with a fresh mixture. This helps maintain a clean fuel system and promotes easier starts.
  2. Regular Air Filter Maintenance: Regularly check and clean or replace the air filter of your STIHL MS 170. A clogged air filter can lead to starting problems and reduced engine performance. To clean the air filter, remove it from the chainsaw and gently tap it to remove loose debris. You can also wash it with warm, soapy water and allow it to dry thoroughly before reinstalling. If it’s significantly damaged or deteriorated, it’s best to replace it with a new one to ensure optimal airflow to the engine.

By addressing these common causes and applying the solutions mentioned above, you can significantly improve your STIHL MS 170’s starting performance. Regular maintenance and proper fuel management are essential to ensure your chainsaw starts reliably every time you need it.

In the next section, we will explore the second common problem – “Loss of Cutting Power” and how to diagnose and resolve it effectively.

Problem 2: Loss of Cutting Power


If you’ve noticed that your STIHL MS 170 is no longer cutting through wood as effortlessly as it once did, there are two primary causes to consider:

  1. Dull or Damaged Chain: The cutting chain of your chainsaw is a critical component. Over time, the chain can become dull due to normal wear and tear or hitting rocks or other hard objects while cutting. A dull chain doesn’t cut efficiently and can put a strain on the engine.
  2. Incorrect Chain Tension: Chain tension is crucial for proper cutting performance. If the chain is too loose, it can lead to reduced cutting power and even pose a safety hazard. On the other hand, if the chain is too tight, it can cause excessive wear on the chain and sprocket.


To address the issue of loss of cutting power in your STIHL MS 170, consider the following solutions:

  1. Sharpening the Chain: Regularly sharpening the cutting chain is essential for maintaining cutting power. You can sharpen the chain using a file guide or an electric sharpener. Follow the manufacturer’s recommendations for the correct file size and angles. Be sure to maintain the proper depth gauge settings as well. A sharp chain not only improves cutting efficiency but also reduces the strain on the engine, extending its life.
  2. Proper Chain Tension Adjustment: Ensure that your chain is tensioned correctly. A loose chain can result in reduced cutting power and a higher risk of kickback. To adjust the chain tension, use the chain tensioning screw provided by the manufacturer. It should allow for a snug fit on the guide bar, with just a bit of sag in the bottom of the chain. Be cautious not to overtighten the chain, as it can lead to excessive wear and damage.

By addressing these common causes and applying the solutions mentioned above, you can restore the cutting power of your STIHL MS 170. Regular chain maintenance, including sharpening and proper tensioning, is key to ensuring your chainsaw performs optimally and efficiently.

In the next section, we’ll explore the third common problem – “Oil Leaks” and provide guidance on diagnosing and resolving these issues.

Problem 3: Oil Leaks


Oil leaks in your STIHL MS 170 chainsaw can be both messy and indicative of underlying issues. To understand and address these leaks, consider the following common causes:

  1. Worn or Damaged Oil Cap: The oil cap, which seals the oil tank of your chainsaw, can deteriorate over time. A damaged or worn oil cap may fail to create a proper seal, leading to oil leaks.
  2. Clogged or Damaged Oiler System: The oiler system is responsible for automatically lubricating the chain and guide bar during operation. If this system is clogged or damaged, it can lead to irregular oil distribution and leaks. Clogs can occur due to sawdust and debris buildup, while damage may result from wear and tear.


To address oil leaks in your STIHL MS 170, you can consider the following solutions:

  1. Replacing the Oil Cap: If the oil cap is worn, damaged, or no longer seals properly, it’s crucial to replace it. You can usually find a compatible replacement part from your local STIHL dealer or authorized service center. Make sure to choose the correct cap designed for your specific model. Once you have the new cap, remove the old one and securely attach the replacement. Ensure it forms a tight seal to prevent further oil leaks.
  2. Cleaning or Repairing the Oiler System: If the oiler system is clogged, it needs to be cleaned to restore proper oil distribution. Start by removing the guide bar and chain and then access the oiler system. Clean any debris, sawdust, or dirt that may be obstructing the system’s operation. It’s essential to be thorough in cleaning to ensure smooth oil flow. If the oiler system is damaged, you may need to seek professional assistance or refer to your chainsaw’s user manual for guidance on repair or replacement. It’s important to address oiler system issues promptly, as they can affect not only oil distribution but also the overall performance and longevity of your chainsaw.

By applying these solutions to address oil leaks, you can keep your STIHL MS 170 in top working condition, minimize mess, and ensure that the chain and guide bar remain well-lubricated during operation.

In the next section, we’ll explore the fourth common problem – “Chainsaw Overheating” and provide guidance on diagnosing and addressing this issue effectively.

Problem 4: Chainsaw Overheating


Chainsaw overheating is a concern that can affect both the performance and lifespan of your STIHL MS 170. To understand the causes of overheating, let’s explore the common factors:

  1. Dirty Cooling Fins: The engine of your STIHL MS 170 has cooling fins that help dissipate heat. Over time, these fins can accumulate dirt, sawdust, and debris, reducing their ability to cool the engine effectively.
  2. Running the Chainsaw Too Hard: Pushing your chainsaw beyond its recommended limits can cause overheating. Continuous operation without allowing the engine to cool down can lead to excessive heat buildup.


To address the issue of chainsaw overheating, consider the following solutions:

  1. Cleaning the Cooling Fins: Periodically inspect and clean the cooling fins of your STIHL MS 170. To do this, ensure the chainsaw is powered off and the engine is cool. Use a soft brush, compressed air, or a similar tool to carefully remove any dirt or debris from the cooling fins. Make sure not to damage the fins during cleaning. Regular maintenance in this regard helps the engine maintain optimal operating temperatures.
  2. Proper Usage and Maintenance: Avoid running the chainsaw too hard or continuously for extended periods. Allow the engine to cool down between tasks. Following the manufacturer’s guidelines for usage, such as not overloading the chainsaw, can prevent overheating issues. Additionally, maintain the air filter, as discussed earlier, to ensure proper airflow to the engine and minimize the risk of overheating.

Remember that overheating can lead to engine damage and decreased performance. By applying these solutions, you can help your STIHL MS 170 operate within safe temperature ranges and extend its lifespan.

In the next section, we’ll explore the fifth common problem – “Unwanted Vibrations” – and provide guidance on diagnosing and resolving this issue effectively.

Problem 5: Unwanted Vibrations


Unwanted vibrations in your STIHL MS 170 chainsaw can not only be uncomfortable to handle but also indicate potential issues. To address these vibrations effectively, it’s essential to understand the common causes:

  1. Loose or Damaged Components: The chainsaw is a complex piece of equipment with many moving parts. Over time, vibrations and normal wear and tear can cause various components, such as the handle, bar nuts, or engine mounts, to become loose or damaged. These loose parts can lead to vibrations during operation.
  2. Worn or Damaged Chain Sprocket: The chain sprocket is responsible for driving the cutting chain. If it becomes worn or damaged, it can cause uneven movements and vibrations during operation.


To address unwanted vibrations in your STIHL MS 170, consider the following solutions:

  1. Checking and Tightening Components: Regularly inspect your chainsaw’s components for any loose or damaged parts. This includes the handle, bar nuts, and engine mounts. If you find any components that are loose or worn, tighten them or replace them as needed. Properly tightened and well-maintained components can significantly reduce unwanted vibrations during operation.
  2. Replacing the Chain Sprocket: If you suspect that the chain sprocket is the cause of the vibrations and it is worn or damaged, it may be necessary to replace it. Consult your chainsaw’s user manual for guidance on the correct replacement part and the replacement process. A new, well-maintained chain sprocket ensures a smoother and more efficient operation of your STIHL MS 170.


Addressing these common causes and applying the solutions mentioned above can help minimize unwanted vibrations, making your chainsaw easier and more comfortable to operate. It’s crucial to maintain and inspect your chainsaw’s components regularly to ensure safe and efficient performance.

With this comprehensive guide to the 5 most common STIHL MS 170 problems, along with their causes and solutions, you’ll be well-prepared to diagnose and address these issues effectively, helping to maintain the longevity and performance of your chainsaw.

In this guide, we’ve explored the five most common problems that can affect your STIHL MS 170 chainsaw, along with their causes and solutions. By addressing these issues promptly and effectively, you can ensure your chainsaw continues to serve you reliably and efficiently.

Remember, regular maintenance, proper usage, and prompt troubleshooting are essential for keeping your STIHL MS 170 in optimal working condition and extending its lifespan. A well-maintained chainsaw is a valuable tool for various outdoor projects, whether you’re a homeowner or a professional. If you have questions or need further assistance, consult your chainsaw’s user manual or your local STIHL dealer or authorized service center for expert guidance and support. Happy cutting!

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