Stihl MS 661 Problems with Symptoms, Reasons, and Solution

by Jack Grover
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Stihl MS 661 Problems

Have you ever encountered Stihl ms 661 problems? Among the most frequent issues is that the chain becomes stuck just on the bar while sawing, and countless hard situations can make it happen.

No offense! As we all know, The MS661 is one of the leading chainsaws in the market. With this power tool, you can cut through what most other chainsaws cannot. However, like any other tool with moving parts, it does have its limitations.

On the other hand, there is always just a solution to this issue, which is a positive factor. All you need to do is learn how to identify these issues and follow some steps or tips on how to solve them.

Stihl Ms 661 Problems And Solutions

It is a good machine, no doubt, but you should check a few things before starting it up. Sometimes you may face Stihl ms661 starting problems. Since the engine is relatively new and has not been used much yet, it will be in the best condition. The cutter bar will be straight, and the blades will be sharp, which will make this machine a pleasure to use.

Stihl ms 661 problemsPossible reasons
Not enough powerDirt engine
Chain slippinglow oil level, dried out bar lubricant, the wrong chain tensioning
Hard StartingA dirty air filter, Dirty fuel tank, Damaged or dirty spark plug, or Incorrectly adjusted carburetor screws.
Poorly aligned teethChain has torn out
Chain overloadingBreakage of chain
Chain breaksthickness

We will now discuss the ms 661 problems, their reasons, and their symptoms. Already we have shown the possible causes as you can see in the table. Let’s start discussing.

Reasons And Solutions Of Not Enough Power

If your chainsaw is not producing enough power, there are some things you can do to make it more efficient.

When your chainsaw is not producing enough power, it could be because the engine is dirty. This could happen if you use the saw in wet conditions or cut damp wood. What’s the remedy? Remove the exhaust system and switch to a different ignition system to ensure proper operation.

If that doesn’t work, then your problem may lie in your fuel tank. Your fuel tank may be too full. There will be no room for extra fuel when this happens, so the engine cannot get enough of its required power to run at max efficiency. To fix this problem, use a hose to siphon out some of the energy from your tank, so there’s ample room for it to continue running smoothly.

Reasons And Solution Of  Chain Slipping

The MS661 has the power to cut through logs of up to 15 inches in diameter and with a 3/8-inch cutting depth. The chain can cut through anything you throw at it. However, this power comes with some limitations, and if the chain slips for any reason, it will just stop working.

Reasons And Solution Of  Poorly Aligned Teeth

It has a vibrating chain bar that cuts the wood by moving back and forth. It does this at a high-speed rate, which can wear out the alignment of your teeth.

This means that one tooth might be over the other. It will make it difficult to cut through a material—or worse, cause you to break your chain.

Luckily, there are steps you can take to fix this problem. You just need to follow these 3 steps:

  • Use the depth gauge tool to measure how much clearance is between two teeth;
  • Remove any excess material from the top jaw with a file; and
  • Turn the depth gauge up or down accordingly so that there is no clearance between two teeth.

Reasons And Solution Of  Hard Starting

When a chainsaw starts, it needs to overcome a certain amount of inertia before the engine is fully engaged and starts spinning. If you have a hard time getting your chainsaw to start, this means that the starting cord is too taut.

If you’re having an issue with your chainsaw starting, we recommend cleaning your air filter and fuel tank and making sure that they are not damaged in any way.


If you still have problems starting your chainsaw after this, we recommend checking for any signs of dust or dirt on the spark plug and adjusting the carburetor screws as needed.

Reasons And Solution Of  Chain Overload

An overloaded chain is one whose inclination and location just on bars are out of alignment. There will be a deep groove on one side of the bar and a very shallow groove on the other side when this happens. The more external track will have a more noticeable curve than the other side.

The first step to fixing this problem is to loosen your bar bracket bolts so you can move your chain cage up or down as needed. The next step is to tighten those same bolts so you can lock in your desired position.

It’s important to note that if you don’t want to constantly readjust your chain cage, then you should alternate between using left and right-handed cuts instead

Reasons And Solution Of Chain Breaks

Chain breaks happen when the chain becomes worn out and breaks. The best way to recognize a chain brake is to inspect your chainsaw for a ticking sound. If you hear a ticking sound, this means that the chain is about to break and may need to be replaced soon. So basically, you can say this is Stihl ms 661 cm problems too.

But other signs that indicate a chain break are:

  • The power of the saw drops;
  • The chain may stop moving or pull off the bar; and
  • Poorly aligned teeth on the chain.

Luckily, you can use some easy solutions to fix a broken chain. One of the most common ways is by using a vice grip so that it doesn’t run away from you while removing it from the saw. Another solution involves using pliers to loosen up the tabs on the side of your saw so that they can slide out easily. When you have removed one of them, use two pliers on either side of the rest of the tabs and then pull them out as well.

When replacing your chainsaw’s chain, remember not to over-tighten it because doing so will cause it to go back too far when cutting, which will lead to another problem down the road.

Frequently Asked Questions(FAQs)

How many cc is a Stihl ms661?

The Stihl MS661 has a 12 amp motor and 16-inch bar and chain. The cc for this model is 13.6. Its cutting speed is 450 rpm, making it perfect for those who want to do cutting in both wet and dry conditions. It also features an auto-oiler, which is very lovely and helpful for those who do a lot of sawing.

How do you calibrate a Stihl 661?

The best way to calibrate a Stihl 661 is with a screwdriver and the proper steps. First, you must remove the spark plug, then the air filter cover. Then, turn the engine over with the starter cord 5-6 times. You should start taking measurements of the gap between the spark plug and cylinder wall. Another way, if you are using a gap gauge, first ensure sufficient space between the piston and cylinder wall. Then make sure that there is enough clearance that no compression occurs when starting your chainsaw. Finally, retorque your spark plug and make sure it.


The MS661 is a versatile and powerful machine. But it can’t do everything—which means there’s always the chance that it might break down. Because every piece of equipment has its own unique set of problems, it’s essential to know what you’re dealing with before attempting a fix.

By following this guide and doing your research, you should be able to get your saw back up and running like new in no time. Hire a professional if you need quiet about repairs or maintenance. When it comes to your Stihl ms 661 problems, don’t be afraid to ask for help.

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