Mid-Mount Drive Belt Is Flopping Around (Video)

[JWR]

To me it looks like the pulley by itself in the center is the belt tensioning pulley. There is an arm under it connected to the spring. The pivot point of the arm is the bolt below the pulley in the picture. Make sure that arm moves freely through it's complete range of movement. A few more ideas: A larger idler pulley would compensate for the longer belt. Maybe all you need is a heavier spring

I disagree that the belt is properly routed/installed. Looks to me like the idler pully (flat surfaced wide pulley that the BACK of the belt rides on) is not tensioning the belt at all. I'd be surprised that it will mow. For heaven's sake install the belt precisely as shown in your owners manual and if you lack one go download it and study the belt routing diagram as well as installation instructions. If the belt is the right belt and you install per the manual it will run right. Yes, there is considerable belt flap when properly installed but NOT like you show in your video.

 

[mkadyz]

I disagree that the belt is properly routed/installed. Looks to me like the idler pully (flat surfaced wide pulley that the BACK of the belt rides on) is not tensioning the belt at all. I'd be surprised that it will mow. For heaven's sake install the belt precisely as shown in your owners manual and if you lack one go download it and study the belt routing diagram as well as installation instructions. If the belt is the right belt and you install per the manual it will run right. Yes, there is considerable belt flap when properly installed but NOT like you show in your video.

The back of the belt is on the idler, and it is most definitely tensioning the belt. The picture isn't very good, but the tractor is in another state and that was the only one I had of the belt routing. I'm going to start with the tension spring, since that has been monkeyed with in the past.

 

[JWR]

The back of the belt is on the idler, and it is most definitely tensioning the belt. The picture isn't very good, but the tractor is in another state and that was the only one I had of the belt routing. I'm going to start with the tension spring, since that has been monkeyed with in the past.

OK, it looks pretty certain that you have no where near enough tension on the belt (which should be provided by that idler pulley which is pulled against the belt by that spring. You just have to debug what is keeping that tensioner from working. I doubt there is anything serious wrong. Good luck with it.

 

[Leejohn]

To me it looks like the pulley by itself in the center is the belt tensioning pulley. There is an arm under it connected to the spring. The pivot point of the arm is the bolt below the pulley in the picture. Make sure that arm moves freely through it's complete range of movement. A few more ideas: A larger idler pulley would compensate for the longer belt. Maybe all you need is a heavier spring

Your 1st part is what he needs to do, it happened to me on my woods 990 and BX2660. It's a bear to pull it off of the shaft to sand clean. I had to make a puller just to pull one of them. Your post is a good one 100% right.

 

[pmsmechanic]

I'm just going to add that I studied the picture of the belt routing and as far as I can see the belt is installed correctly. The blades need to turn clockwise and you never take up slack in a belt on the tension (pulling) side of the power flow (for lack of a better word). You always take up slack on the return side of the belt and that's where the idler is. The belt is routed correctly, so that means that the idler is the issue. That's the logic for my conclusion.