RC72-28 mower

[nbmech]

Hello, My mower deck has a blade that is loose. The blade near the discharg spins freely and when I try to cut grass a very loud whining noise comes from it. The bolt seems to be tight. Any ideas
Thanks

 

[Eric McCarthy]

Most blades have to be torqed to a certaint spec so get your manual and see what it calls for and buy a torq wrench and make sure its as tight as it needs to be. What you may think is tight by had is not nearly as close to the torq specs.

 

[cmorningstar01]

If after making sure the blade bolt is torqued correctly as Eric has suggested and it still spins then you may have sheared a key in either the blade adapter(sometimes called a blade holder) or the sheave(pulley) hub. You will need to determine exactly where the slip is occurring.

 

[Fudgecreek]

The blade is held against the spindle with cupped ( Belleville) washers. I suspect that either your washers are not centered on the spindle or the cup has worn out. If you have two washers, change which one is against the blade with the other. Some spindle / blade / bolt combinations will allow for an additional flat washer that will compress the cupped ones more.

 

[ipz2222]

Just had a similar problem, put new (aftermarket blades on a bx22) . First time around, noticed the noise and less grass comeing out the discharge. Problem was, the new blades were thinner and the bolt was comeing up and tightening against the spindle and not the blade. Added another washer on top of the blade, problem fixed...

 

[DFE]

When something causes a blade to slip, the belleville washers get hot and lose their temper. The proper fix is new belleville washers. Last ones I bought from Kubota dealer were around $15 each, and each blades uses 2 in parallel.

I sure would like to find a good source, and / or specs on the washers.