Deck Vibration

[Ol'Red 7]

Hi guys, I have a 36" RD deck that has a lot of vibration in it. I think the bearing have been replaced with an aftermarket one. They are non greasable and had a D-shape on both ends. I've taken the two outer ones off to inspect them and they seem fine (I couldn't get the middle pulley off to look at the middle bearing). Do you guys think its most likely a bearing or is there something else I can check before I take it all back apart? I felt the bearings after I had cut for about 2 hours and they were cool. I also will double check, but I'm sure the blades are balanced. Any help would be appreciated

[daveoman1966 3,841]

Release the belt and check the IDLER PULLEY.  It must spin freely with NO WOBBLE or slop in the bearing.  Be sure the apparatus to maintain belt tension works freely too.  The tensioner arm has to slide easily back and forth.  Don't grease this sliding arm...that only colllects dirt and debris.  Leave it dry. 

If not that, then it is the center spindle bearing that you couldn't get apart.  It can be a beast.... Soak it for hours and hours. 

Edited May 19, 2014 by daveoman1966

[slammer302 2,156]

I noticed on my 36"rd deck that the belt going to the deck from the pto will make the mower shake alot if its not right

[daveoman1966 3,841]

That's right....  check the tension of the PTO drive belt, AND the two pulleys of the Mule Drive.  Either one of them may be the cause of vibration, or ...if the belt is too loose, that MAY also cause it.  It should deflect about 1/2" midway between PTO and mule drive.

[GlenPettit 1,717]

If the same belt has been on the mower for 10-15 years, by always being under tension it probably has stretched where it can't be tightened any more . . . this is very common with long belts.  It should be replaced, I'ld strongly recommend using only Wheel Horse-TORO brand belts, even though they are made by Gates, they are made to a different & higher standard, and also have a unique angle (Agricultural), well worth 10-20% more for maybe 2-3 times the life.  I found that eBay seems to have the best prices, but it takes a week.  If we were all smart, we would release the tension after every mowing, but none of us do that, I don't think.

[jdmitchjr@6dlam.com 5]

On another brand mower deck, I had a vibration that I could not source.  I even went so far as to swap out each of the spindles with a new one.  The idler pulley was slapping back and forth.  Then I checked the belt carefully.  It looked fine but on closer inspection about a 4" section was worn or melted thinner.  That slightly thinner cross section was the cause of the vibration.  A new belt fixed the problem.  Something must have hung for a moment and the belt stopped to melt down.  So since you have an old belt, replacing the belt is probably a good idea.

 

B/R

 

John

[groundhog47 347]

If you have any sweet gum trees around or other trees with something that would get in any of the pulley grooves that will also cause a heck of vibration. Thought I broke a blade and only a gum ball, hah! I was thankful it wasn't sump'in worse. "Who'da thunk it?"

[Ol'Red 7]

Thanks for all of the replies. I will inspect the belt and idler pulley. The PTO belt was new when I got the mower last year so it should be good. I'll let you all know what I come up with.

[Ol'Red 7]

Small update (haven't had time to check everything you all mentioned out)... I cut with it Friday evening and reduced the tension of the PTO drive belt and it got a lot better. It still has a small vibration in it. Not sure if this means its in the mule drive or the center spindle bearing. I'll keep you all updated

[leeave96 490]

Is it possible your blades are out of balance?