How do you replace the chainsaw tension screw on a stihl 041 farm boss chainsaw?

First remove the clutch cover to expose the clutch, bar studs and area of the tensioner.

Next you need to remove the bar studs. To do this tighten two nuts agains each other on the bar stud, then put a wrench on the lower nut and use it to loosen the whole stud. Repeat for the 2nd bar stud. Sometimes if you are lucky you can use vice grips on the shoulder of the stud to unscrew them, be careful not to damage the threads.

After removing the bar studs, the inner bar plate and tensioner assembly lift right out.

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