Parts

Parts and tools included in the MS170 how-to video.

• Clutch Assembly - 1123 160 2050
• Chain Sprocket 3/8" Picco 6T - 1123 640 2003
• Clutch Shoe - 1129 162 0800
• 13/19mm Combination Plug/Bolt Spanner - 902 1361
• Locking Strip - 0000 893 5904
• N/G Torx Wrench/Plug Spanner (13mm & 19mm) - 410 250

Transcript

In this video, we show you how to change the Clutch on a Stihl MS170.

Health & Safety Warning - Please ensure that you have safely prepared the machine and workspace. If you are unsure about any aspect of the task please seek professional advice.

Changing the Clutch on a Stihl MS170 Chainsaw

Today, we're going to change the Clutch on a Stihl MS170 Chainsaw. Make sure the chain is free before starting.

Step 1: Loosen the Sprocket Cover

Use a 19mm Hex Socket Spanner to loosen the two nuts that hold on the sprocket cover on the side of the machine. Then use a screwdriver to loosen the chain tensioning screw between the guide bar and the machine, you will notice the chain will begin to become slack.

Continue to unscrew the two sprocket cover nuts on the side of the machine. This will allow you to remove the casing, completely freeing the chain and bar.

Step 2: Remove the Chain Sprocket

Using Pliers remove the circlip inside the chain sprocket. You can then remove the sprocket washer and chain sprocket. You may also want to remove the sprocket bearing so it doesn't get lost.

Step 3: Access the Machine's Interior

Using a flathead screwdriver release the shroud by turning it clockwise. You can now remove the shroud. By hand remove the air filter. Using a 19mm hex socket spanner loosen the spark plug. Once it's loose, you can remove it by hand. Now insert the piston stop through the spark plug entry. This will lock the crank, allowing you to unscrew the clutch.

Step 4: Remove and Check the Clutch

Using a 19mm spanner push the nut clockwise to loosen the clutch. Once loosened, spin clockwise to remove the clutch. Check your clutch for wear, especially on the springs. Replace if necessary.

Step 5: Reassemble the Machine

Spin the clutch onto the machine by turning it anti-clockwise. Tighten the clutch back onto the machine, you need the piston stop to still be in place to tighten. Place the sprocket bearing over the clutch, and fix the chain sprocket on top. Relocate the sprocket washer on top of the chain sprocket.

Then use a pair of pliers to squeeze the circlip back into place. By hand screw the spark plug back in, and return to tighten with 19mm spanner. Place your air filter back into position. Fix your shroud back into place, and secure by turning the plastic bolt anti-clockwise.

Step 6: Reattach the Chain

When placing the chain back on to the guide bar make sure the cutting edge, highlighted in red, is facing away from the body of the machine on the top edge of the guide bar. This means that the cutting edge should be facing in direction of the blades rotation. Feed the chain around the bar and make sure it's seated correctly.

Make sure the chain moves in a smooth motion and doesn't snag. Place the chain around the chain sprocket. Make sure the two screws are seated in the opening in the guide bar. Place the casing back on and hand screw on the two nuts.

Using the screwdriver to tighten the chain tensioning screw between the guide bar and the machine. Once together, make sure the chain is moving smoothly and isn't too tight and doesn't have excessive slack.

Conclusion:

That's how you change the Clutch on the Stihl MS170. All the parts & tools needed for this task are listed in the description below.