In this video, we show you how to change the drive belt on a Stihl TS420 disc cutter.

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.

Transcript

Today, we're going to change the drive belt on a Stihl TS420 cut off saw. First of all, use a torx spanner to remove the screw that secures the water connector from the underside of the machine. This will provide better access to the recoil. Next, use a 19mm Hex Socket Spanner, turning it anti-clockwise to loosen the tension of the belt. Once this is done, use a 13mm Hex Socket Spanner to loosen the three nuts that secure the recoil assembly. Then revisit each nut and completely remove them, freeing the recoil from the machine.Using the torx spanner, remove the screw that secures the nose guard to the arm.Once the nose guard is off, use the 19mm Hex Socket Spanner, turning it anti-clockwise to further loosen the tension of the belt. Completely remove the front of the saw to free the belt. If you are unsure whether to replace the belt, inspect it by eye and with your fingers to check for wear & splits in the belt. Bear in mind that the belt may have stretched and the rubber may have lost it's goodness. To fit the replacement belt, locate it over the clutch, making sure the its sitting in the grooves correctly, to prevent damage to the belt. Then feed the belt back through the arm, relocating the arm back in position around the studs. Feed the belt back around the pulley. Slowly turning the pulley will help you easily locate the belt. Make sure the blade turns with a smooth motion. Relocate the casing onto the arm and use the torx spanner to fix this in place. Make sure the screw is secure without over tightening it, as the casing is only plastic. Locate the recoil assembly onto the machine, loosely turn each nut a few times.Then return to tighten each nut with the 13mm spanner, again, be careful not to split the plastic when tightening. Then re-tension of the belt using the 19mm Hex Socket Spanner. Don't forget to fix the water connector back into place under the machine using the torx spanner.That's how you change the drive belt on the Stihl TS420. All the parts & tools needed for this task are listed in the description below.

Parts

Parts and tools included in the TS420 disc cutter how-to video.

• Genuine Drive Belt - 9490 000 7901
• Non Genuine Drive Belt - 410 260
• Hexagon Nut M8 - 9220 260 1100
• Screw IS-D5x20 - 0000 951 1100
• Genuine Torx Wrench/Plug Spanner - 4224 890 3400
• Non Genuine Torx Wrench/Plug Spanner - 410 250