Bush Hog violently shaking

[Hay Dude]

That’s not as easy. I’d pull the shielding off and hook PTO shaft back up, then slowly spin up the mower at low rpm and take a look at the stub. See if it wobbles.

When you say “PTO shaft not bent”, did you remove the plastic shielding? It could be bent under the shielding.

 

[lwarner901]

Did you happen to notice one of the blades folded forward, but not stuck in place like with the sharpened side towards the pan when you checked the blades..?? If you had to pull the blade so it's straight out like it should be, then spun, that could have been the problem, knuckled ahead, and it makes it hard for centrifugal force to straighten out to cut and makes it unbalanced.

Awesome thought! I will pull it back up in the morning and check that!

 

[sandman2234]

I have had blades cross and get stuck before. Spinning them while crossed and they shake violently, but usually come uncrossed and all the vibrations stop.
David from jax

 

[jfsawatzky]

I have had blades cross and get stuck before. Spinning them while crossed and they shake violently, but usually come uncrossed and all the vibrations stop.
David from jax

Similar to the above comment, I managed to bind some small piece of wood between the blade and housing that caused one blade to stop rotating and throw it off balance. Was a pita to remove that piece of wood.

 

[Hay Dude]

If you tried to climb out of a steep ditch and the prop shaft had no more room to go up, you could have tweaked something. One way to eliminate the tractor is to hook the BH up to another tractor. But I think its something in the BH, starting at the blades and up to the prop shaft.

To eliminate your tractor, hook something else up to it and see if it shakes that attachment.

 

[Fladogman]

I would try disconnecting the drive Link lift the mower , crawl underneath and spin the blades and look for some out of place first

 

[lwarner901]

That’s not as easy. I’d pull the shielding off and hook PTO shaft back up, then slowly spin up the mower at low rpm and take a look at the stub. See if it wobbles.

When you say “PTO shaft not bent”, did you remove the plastic shielding? It could be bent under the shielding.

My PTO shaft is a connected 2 piece one that slides inside the other, I pulled back the plastic shielding and slid it in & out of each other no problem. I’m going to try to hook up another 3 pt this morning AND look underneath again to see if all the blades are turned at the same angle

 

[Hay Dude]

My PTO shaft is a connected 2 piece one that slides inside the other, I pulled back the plastic shielding and slid it in & out of each other no problem.

The plastic shielding may slide easily, but the steel prop shaft inside might be slightly tweaked.

I’m going to try to hook up another 3 pt this morning AND look underneath again to see if all the blades are turned at the same angle

What you might want to inspect is the input shaft to the mower.

Also inspect the prop shaft U-joints. When you put the mower on an extreme angle, it may have tweaked a U-joint.

Start with the simple/easy things like bent blades, or blades that are not swinging properly, then move to prop shaft, u joints, then look at the splined input shaft on the mower

 

[jyoutz]

Did you happen to notice one of the blades folded forward, but not stuck in place like with the sharpened side towards the pan when you checked the blades..?? If you had to pull the blade so it's straight out like it should be, then spun, that could have been the problem, knuckled ahead, and it makes it hard for centrifugal force to straighten out to cut and makes it unbalanced.

I suspect that’s what the situation is.