Belt Slap

[The flying milkman]

Just last Friday I purchased a new Huskvarna Ts142 mower.from the local Lowes. It replaced a 36-year-old MTD that I could no longer patch together.
I love it so far, it does what it was designed to. But I do have one problem when you engage the cutting blades the noise and the vibration coming from the belt slapping under you are unnerving at best. That old MTD never made that much of a racket on its worst day. Is this a common problem with this mower or could there be a wrong belt application or worse?

 

[Rivets]

Sounds to me like you may have a missing tensioner spring, bad spindle, bad spindle pulley or bad idler arm or pulleys. If is thank new I would contact Lowe’s and find out who does their warranty work. Let them do the troubleshooting, before you start replacing parts.