A list of 14 Stihl MS 661 C-M common problems and fixes

The Stihl MS 661 C-M is a great chainsaw, but like all chainsaws, it can have some problems from time to time. In this blog post, we’ll take a look at some of the possible problems you might encounter with your Stihl MS 661 C-M chainsaw, as well as some solutions to those problems.

Stihl MS 661 C-M: Frequently Asked Questiuons

When did the Stihl MS 661 C-M come out?

The Stihl MS 661 C-M was first released in 2013. It is a powerful saw that is designed for professional use. It has a lot of features that make it a great saw for those who need a powerful tool to get the job done.

What CC is a Stihl MS 661 C-M?

The CC of a Stihl MS 661 C-M is 91.6. This means that the saw is capable of cutting through 91.6 cubic centimeters of wood in a single minute. The MS 661 C-M is a powerful saw that is designed for professional use. It is one of the most popular saws among professional loggers and arborists.

What’s the MS 661 C-M specification?

  • Displacement: 91,1 cm³
  • Power output: 5,4/7,3 kW/bhp
  • Weight: 7,4 kg
  • Power-to-weight ratio: 1,4 kg/kW
  • Sound pressure level: 105 dB(A)
  • Sound power level: 118 dB(A)
  • Vibration level left/right: 6,9/5,6 m/s²
  • Saw chain pitch: 3/8″
  • STIHL Oilomatic saw chain type: Rapid Super (RS)

How many horsepower does a MS 661 C-M have?

The Stihl MS 661 C-M is a gas-powered chain saw designed for general use. It has a peak output of 6.3 horsepower and can handle most tasks a homeowner would need it for. However, there are a few problems that can occur with this saw, and some easy solutions.

Stihl MS 661 C-M

How much does a Stihl 661 C-M weight?

One of which is its weight; at just over 26 pounds, this machine can be heavy to carry around. To help offset the weight of the MS 661 C-M, many homeowners opt to use a backpack attachment or an optional wheeled cart. When using either option, it’s important to make sure the machine is properly balanced and secure so as not to cause strain on your back or arms.

What chain does the Stihl 661 C-M have from the factory?

The Stihl MS 661 C-M comes with a 3/8″ PMC3 saw chain from the factory. This chain is designed for use with a saw with a guide bar that is 20″ or less in length.

How big of a bar can you put on a Stihl MS661 C-M?

The answer to this question depends on a few factors, such as the size of the saw and the type of bar you are using. For example, if you are using a 16″ bar, you could probably put a 36″ bar on a Stihl MS 661 C-M. However, if you are using a 20″ bar, you might be limited to a 28″ or 30″ bar.

What’s the Stihl MS661 C-M max bar length?

The MS 661 C-M has a maximum bar length of 36 inches, which means that it can handle even the most challenging tasks. If you need a saw that can handle anything, the Stihl MS 661 C-M is the saw for you.

How much is a Stihl MS 661 C-M?

A Stihl MS 661 C-M chain saw typically retails for around $1,500. However, prices may vary depending on the retailer, location, and other factors. If you want to know more details you can search on the official website.

Where to find Stihl MS 661 C-M for sale?

There are a few ways that you can find the Stihl MS 661 C-M for sale. You can either go to a Stihl dealer or you can find it online. If you go to a Stihl dealer, they will more than likely have it in stock. If you cannot find it at a Stihl dealer, then your next best option would be to look online. You can find it online through different retailers or even through online auctions.

Does the MS 661 C-M come with a case?

The Stihl MS 661 C-M is a gas-powered chain saw that comes with a case. However, there have been reports of the case breaking. If you are planning on purchasing the saw, it is important to ensure that you purchase a case that will fit the saw properly. Additionally, make sure that the saw has enough fuel to last during use.

Stihl MS 661 C-M

Stihl MS 661 C-M: Guidance and Instructions

How to adjust the carburetor on a MS 661 CM?

The Stihl MS 661 C-M carburetor can be adjusted to fine tune the performance of the engine. There are a few different ways to adjust the carburetor on this mower. Follow these instructions to adjust the carburetor:

  1. Locate and remove the fuel tank cap and unscrew the filler neck.
  2. Remove the air filter cover by gently prying it off with a flat head screwdriver.
  3. Be careful not to lose screws or other pieces while doing this!
  4. Slide the carburetor bowl off of the engine block. The bowl should still be attached to one end of the throttle slide by a small spring clip. 
  5. Inspect both jets and make sure they are clean and free of debris. Be sure to replace jets if they become clogged or if your mower doesn’t run as well as it should now that you have cleaned everything up!
  6. Tighten them until they just start.

How to replace bar oil pump for Stihl MS 661 CM?

  1. Draining the oil tank. Before you start working on the bar oil pump, you need to drain the oil tank. To do this, remove the oil cap and unscrew the oil hose from the pump. Then, let the oil drain out completely.
  2. Accessing the bar oil pump. To access the bar oil pump, you need to remove the sprocket cover and the bar. Once the cover and bar are removed, you will be able to see the pump.
  3. Replacing the bar oil pump. To replace the bar oil pump, simply remove the old pump and install the new one in its place. Make sure that the new pump is properly seated and that all the connections are tight.
  4. Refilling the oil tank. Once the new pump is installed, you can now refill the oil tank. Screw the oil hose back into the pump and then replace the oil cap.

How to adjust the chain tensioner on Stihl MS 661 CM?

If your Stihl MS 661 C-M chainsaw is producing too much vibration, it may be due to the chain tensioner. The tensioner is a small, metal piece located at the front of the saw near the cutting chain.

To adjust the tensioner, first loosen the two screws that hold it in place. Then, use a flathead screwdriver to turn the tensioner clockwise or counterclockwise until the desired tension is achieved. Finally, retighten the screws and test the saw to see if the vibration has been reduced.

What fuel mix to use for the Stihl MS 661 CM?

When using gasoline with this chainsaw, it’s important to use a fuel mixture that is designed specifically for this type of equipment. In general, a mixture that is between 9 and 11% ethanol will work well with the MS 661 C-M. This mixture will provide plenty of power while also being easy on the engine.

If you’re planning on using diesel with your MS 661 C-M, be sure to use a fuel blend that is specifically made for chain saws. A blend that is between 5 and 7% diesel should work well in this case. This mixture will provide plenty of power while also being relatively safe for the engine.

Stihl MS 661 C-M: Troubleshootings

1. Stihl 661 C-M: Suddenly stop while cutting

If you’re using a Stihl MS 661 C-M chainsaw and it suddenly stops while you’re cutting, there are a few potential causes.

  1. First, check the chain to make sure it’s not damaged or dull. If the chain is damaged or dull, it can cause the saw to stop abruptly.
  2. Second, check the fuel mix. If the fuel mix is too lean, it can cause the engine to stall. Third, check the air filter. If the air filter is dirty, it can restrict air flow to the engine and cause it to stall.
  3. Finally, make sure the spark plug is clean and gap is set correctly. If the spark plug is fouled or the gap is incorrect, it can cause the engine to misfire and stall.

2. Stihl 661 C-M: Engine loses power gradually

The engine of your Stihl MS C-M might lose power gradually. This can be caused by a number of things, but the most common cause is that the engine’s oil has become dirty. If this is the case, you’ll need to take some simple steps to clean the engine and restore its power.

To clean the engine, start by draining any excess oil from the crankcase using a suitable container. Next, use a degreaser to remove all of the dirt and grime from inside the engine. Finally, fill up the crankcase with fresh oil and replace any parts that were damaged in the cleaning process.

3. Stihl 661 C-M: The chain tends to be loose

There seems to be an issue with the chain on the MS 661 C-M pruner. It tends to be loose and require a lot of force to move the chain up and down. This can lead to problems such as missed cuts, which can be quite frustrating. The good news is that there are easy solutions for fixing this problem. Here are 3 tips to resolving your MS C-M chain issues:

  1. Inspect the connection between the chain and the sprocket: If the connection between the chain and sprocket is loose, it will cause difficulty in moving the chain up and down. To fix this, you will need to tighten up the connection with a wrench. Make sure not to overdo it, though – too much torque could damage your tool.
  2. Check if there’s debris or sand blocking the sprocket: If there’s debris or sand blocking the sprocket, it will also cause difficulty in moving the chain up and down. To clear out any obstructions, you will need to use a wire brush or an angle grinder. Be very careful not to damage your tool in the process!
  3. Check if there’s excess oil on the chainsaw: If there’s excess oil on the chainsaw, it will also cause difficulty in moving the chain up and down. Clean off any excess oil with a damp cloth before trying again to move the chain up and down. Make sure you do this after every use.

Stihl MS 661 C-M


If you’re looking for a powerful and reliable chainsaw, the Stihl MS 661 C-M is a great option. However, like any chainsaw, it’s not without its possible problems. Fortunately, there are solutions to all of these problems. With a little bit of knowledge and some basic tools, you can keep your Stihl MS 661 C-M running like new.