Product Description
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Milwaukee Chain Tensioner Main Screw
Model Number: 05-89-0018
The Milwaukee 05-89-0018 is a genuine OEM Chain Tensioner Main Screw for compatible Milwaukee chainsaw and pole saw attachments including the 49-16-2720 Pole Saw Attachment and the M18 FUEL QUIK-LOK Power Head (2825-20) system. The chain tensioner main screw is the threaded body component of the tensioner assembly that houses and interfaces with the chain tensioner adjustment screw — together they drive the chain tensioning post forward or backward to position the guide bar and set the correct chain tension. As the adjustment screw is turned, it threads through the main screw body to push the tensioning post and bar into the correctly tensioned position. A stripped, corroded, or damaged main screw that can no longer properly interface with the adjustment screw or guide the tensioning post requires replacement to restore accurate, reliable chain tension adjustment on the saw.
Using a genuine Milwaukee OEM chain tensioner main screw ensures the correct thread specification, length, and dimensional fit within the tensioner assembly for the compatible attachment it serves. Non-OEM main screws may not match the original thread profile or body dimensions, leading to inconsistent tensioner movement or inadequate chain tension adjustment. Always verify your catalog number and serial number on Milwaukee's website before ordering to confirm this is the correct main screw for your specific unit.
