Grading Brush cutter blade bushing failure for 422

[BobRip]

There is a bushing in each blade on the 422 brush cutter. The bolt goes through the bushing which is in a hole in the blade. After much use, I have taken blades off to sharpen them and have had these bushings fall apart. Has anyone else had this problem? Is there a way to extend their life? Would it help to lubricate them? It might be a good idea to keep a couple of spares handy.

Bob Rip

 

[MuncyBob]

This sounds like the same attachment set up for the finish mower blades too?? I just had my blades off for sharpening and didn't see any wear on the bushings...I would guess that I have around 75 hours on the mower...

 

[MossRoad]

Here's a link to a post about our 4' brush hog for our PT425. I disassembled it and re-assembbled it. There are lots of pictures in the posts that are worth looking at. Hope this helps.

 

[MuncyBob]

Finish mower blade attachment looks nothing like those! I was surprised to see that the blades attach by just a single bolt assembly that is not keyed.

 

[MossRoad]

On a brush cutter, the blades have to swing on the bushings that the one bolt goes through so that if you hit something really hard, it will swing past it. If it were rigid, it would destroy itself.

Think of it this way... would you cut off the front of your lawnmower deck to expose the tips of the spinning blades, then push them up against one to two inch diameter trees and the occasional rock? They would shatter or your shaft would bend, etc...