Mowing Grease and mower vibration

[ewoz]

I have a BX2230 with a 54 inch mid-mount mower deck with 35 hours on it. It recently developed a vibration problem. It used to run much smoother than what it does now. I took the belt off the pullys and noticed that the left outer blade spins rough compared to the right outer blade. It makes me think that I have bad bearings on the left blade assembly. I took it apart to inspect the bearings but could not find anything wrong with them. They seem to spin smooth when everything is apart but when it is together it does not spin so smooth.

I do not understand how the bearings get grease. There is a grease nipple on the top or the shaft. Grease enters at the nipple and exits the shaft through a hole in the side of the shaft that is between the upper bearing and the upper bearing seal? How does grease get to the lower bearing? Does anyone have any insight on this? Also has anyone had vibraqtion problems with BX series mowers?

Thanks.

 

[rosey]

Is it possible that you hit a rock causing the blade to become out of balance???........in any event with the tractor only having 35 hrs on it and still under warranty .........if it were mine I would contact the dealer and have them take care of the problem.

 

[Volfandt]

I have the 60" MMM and it is smooth and quiet.

There have been several reports of MMM's being delivered with very little grease in them. Your's may have been one and if so the bearing may be toast.

When I 1st took delivery of my MMM, it was winter so I removed the blades and caps then greased the spindles. It took quite a bit of grease to finally get the grease to squirt out of the bottom of the spindle. Inorder for the grease to have squirted out the bottom it had to go through the lower bearing. Perhaps theres another hole towards the bottom of the spindle shaft.

As for your vibration, it could be the bearing is bad but with so few hrs that would be unusual. You could repack the bearing and retry it.
Other causes could be the blade is out of balance which is easy to test for. The spindle could be bent or there could be a bad spot in the belt.
Generally, you would have had to have hit something hard inorder to bend the shaft or blade so if you don't recall this happening then I'd say the bearing is the problem.

You may try installing it in another spindle to see if it tighten's up when it's reassembled and/or try a known good bearing in it's place on the suspected spindle.

Good luck
Volfandt

 

[orangebluegreen]

I have limited experience so far with the Kubota deck, but it should be about the same symptom wise as my old Craftsman which I’ve used 14 years.


A growl with a higher frequency vibration was usually bearings. A heavier shaking type of vibration was usually a cut in the belt where the belt was about to break, inspect the belt closely, sometimes a sharp object gets between a pulley and the belt causing a slice. If you have recently sharpened the blades and notice a vibration after putting them back in use, you would suspect blade balance. I have not experienced blades going out of balance on their own because they usually wear evenly. Obviously a hard hit that would bend a shaft or pulley could cause vibration....also check the grease and universal joints on the PTO shaft.

 

[Buckeyeman]

It took quite a bit of grease to finally get the grease to squirt out of the bottom of the spindle. Inorder for the grease to have squirted out the bottom it had to go through the lower bearing. Perhaps theres another hole towards the bottom of the spindle shaft.
Volfandt

When I took delivery of my B7610 w/60"MMM deck the owner of the dealership was going over everything with me and he said "don't go overboard pumping away on the grease gun when you are greasing the pullies on the deck because you will blow the seals underneath". He told me to just put a little bit of grease in at a time. He said he sees it all the time in his service dept. where guys get crazy with the grease gun, and have to have the seals replaced.

 

[ewoz]

Thanks for the replies. I may have chopped some sod at about the time I noticed the vibration, but it was nothing worse than I have done in the past. There is a definate difference in how smoothly the the left and right blades rotate when they are rotated by hand with the belt off. The right hand one is unbelievably smooth while the left hand one has some definate roughness associated with it. I am guessing that the vibration that I am experiencing is due to this but it is not necessarily the case. There may be a bad belt or bent shaft or unbalanced blade. Inspecting the belt for cuts that may have occured by something getting caught between the pully and the belt is a good idea, I'm going to do that. I think I will also carefully fill the shaft with grease until I see grease coming out the seals as Volfandt described while heeding the advice of Buckeyeman. If the bearing is still rough it will be time for a call to the dealer. It is still under warranty...