Vibration in Woods rotary mower

[MESSMAKER]

I am noticing some vibration that I can feel in the steering wheel. It seems to come and go or at least is more intense at different RPMs. I have checked the blades, but seem to look OK. The stump jumper has a couple small dents, but nothing major. I am beginning to think that maybe I have a bent output shaft. How do I check this? What else could it be?

 

[nyone]

Remove the shield and spin the shaft. Have you checked the bearings in the gearbox or spun the cutter by hand and watched for anything not looking true?

 

[bearthebruce]

I don't have a Woods brush cutter.. but I did pick up a small piece of fence wire at one point. Was just enough to get under one blade and slow it's spin. I would hit a larger piece of brush and it would take a while for the mower to spin that slow moving blade back out.. Vibrations would ride through the tractor.

I finally crawled under and checked things in detail.. found the one blade not wanting to spin freely. Took it apart and found the small piece of wire wedged between the blade and the stump jumper plate.. removed the wire, re-assembled, and no more issue.

Could you have something like I had?

 

[zzvyb6]

Could be a flat section worn on the drive belt.

 

[Zebrafive]

Bad U-joint(s) in the PTO shaft?
Bent PTO shaft (from raising too high and shaft hitting deck) The shaft could be bent inside the shield and not look bent with the shield on.

If the output shaft is bent, you might see the blades and/or stump jumper not following a lever path. DO NOT CHECK WITH TRACTOR POWERING THE CUTTER! Have someone turn the PTO shaft while you watch.

 

[jshwhite]

Not sure what model woods you have, but my 6ft rotary was bad about vibrating. The blade pivots would stick a little and make one blade slightly off center. If I mowed over some limbs or a small tree or something to shake it around, it would smooth out. Check those bolts that hold the blades on and make sure they're not rusted. Grab each blade and make sure it swings freely. Squirt some power blaster in there to loosen it up a little.

 

[Hay Dude]

A little vibration is normal. It’s a tractor and a Bush hog.
Come on mannnnn!