S185 Drive Belt Slippage

[BentSpace]

My S185 started squeaking and then stops moving during different maneuvers such as turning in one place or going up a steep hill. Is this indicative of the drive belt slipping? I looked at the pulley tensioner and it looks like the pointer is still at the 3 o’clock position, so does that mean it’s still at the proper tension or should I try to readjust it? The drive belt shield only has 1 mounting clip left out of the 3, does this matter? What is the purpose of the shield? Also it looks pretty dusty back there, could that be causing the slippage?

 

[Tazza]

The cover is really just there to keep hands out when it's running.
The dust could just be dirt, or it could be wear from the belt too.
Even though the pointer is right, give the belt a push, see if there is any play in it, the pointer does not always work as it should, they do break.
The belt could also be too worn and bottoming out preventing it from making good contact.
There is no oil or grease on the belt?