View Full Version : Deck belt derailing

07-28-2011, 10:09 PM

We have a 2006 Toro Z400 48" mower with 23HP Kawasaki. Today the deck belt started derailing itself for no apparent reason. We put it back on but continued to happen again and again.

The right side (discharge) idler pulley closest to front of the deck was a little loose. We retightened and reinstalled the belt. Problem persists.

At the advice of my dealer, we started looking at the idler pulley with the tensioner spring (left side, slightly forward of rear tire). We replaced this idler pulley with another identical brand new one. All other parts seem secure and working properly. Problem persists.

Please Help!

07-28-2011, 10:17 PM
In most cases once a belt rolls off at speed it puts a twist in the inner cords, Once it's twisted it will never stay on.

If you have all pulleys lined up and tight now, Replace the belt with a new one.

07-28-2011, 10:38 PM
I threw a belt, like restrorob says once you get a twist in a belt it is history. Try changing it and see what happens..

07-29-2011, 02:10 AM
Before installing that brand new $80 belt I would recommend checking all
pulleys and spindles for bearing wear, best time to do it, between belts.