Wheel Horse 312-8 weird deck spindle problem

[skyler25 3]

Hi, I have a 312-8 with a 48" deck. The right spindle slowed to roughly 1/2 speed while mowing. I could tell as the right grease fitting was spinning slow and cutting not so good on that side. I just greased it before I started and heard a thud or something after a few minutes. Don't think I hit anything. Took off the deck and covers. One deck belt drives all pulleys. Everything looks fine. Idler, spring, tension, etc. I just don't see any damage. I held the spindle with my hand and the blade seems well connected. Everything moves and spins freely. any guesses before I put it back on? Thanks, Skyler

[daveoman1966 3,738]

If this is the style with a woodruff key in the top pulley, you MAY have sheared it or it suffered from being loose for a while.  If it is a newer type spindle that doesn't use the woodruff key then MAYBE the top nut has worked itself loose, or the pulley center has ...somehow... worn to be out-of-round and, thereby, became loose. 
Before you button it up, pinch the belt to ensure that the spring tension arm and pulley are not STUCK.  Actually, that is the 1st thing to check.  That flat tension arm and pulley whould be able to bounce back and forth freely, with no restriction at all.    

[Ed Kennell 37,495]

Stand the deck vertical  on the back wheels so you can see the top and bottom. Make sure it is fastened to something so it cannot fall on you.   Then use a wooden block to lock the questionable blade to the deck.  With gloves on, turn one of the other blades and note what is not turning.  Belt, pulley ,or  spindle  ?

Oh...pardon my manners Skyler.      TO  

[953 nut 54,383]

    I had a similar problem a couple of years back, in my case it turned out that the deck body had cracked about 2/3 of the way around the mandrel, right where it was stamped out and you couldn't see it under the pulley. I removed the entire assembly and welded the piece back in place; works like new.

Hope you can fix it without too much problem.

[skyler25 3]

Ok. Thanks to all and also the warm welcome. It looks like I'll be able to narrow it down with the block idea. Then (in a couple days) I will report back with the news. Yes, I hope it is nothing too complicated. Hopefully it will just be a matter of buying a spray can of "Spindle Fix" from the local dealer. Once again, Thanks. Skyler

[953 nut 54,383]

I didn't know "Spindle Fix" came in a spray can, I have always used a roller.   

[skyler25 3]

oops, sorry.

[skyler25 3]

i all, just a quick note. I have checked the spindles by using a block as suggested. Results still have me guessing some. Blocking the center blade locks up everything tight. There is only the belt slipping with other blades blocked. Of course turning it (blade) in the cutting direction I saw the nut coming loose on the slow spindle. That's about all I seen trying many blades and directions. Both side blades have some belt slippage. Don't know why it locks up so good with the center blocked.I understand turning the blade or spindle can give different results. So I tightened the bolts, and will clean the pulleys and put it back on and re-post. But maybe it could use a new belt. Sorry this is unclear. Skyler