Originally Posted by ProStreetCamaro
Blade belt jumped off mine when I engaged the blades on the first lawn of the day yesterday. Looked at it and I dont see any wear or marks on the belt so I laid down and put it back on. Worked fine rest of the day and again today. Not sure what caused it. I personally think the tensioner needs to be snugged up a bit.
Mine did the same thing for the main deck drive belt. I added a little additional tension to the spring on the idler. Later I talked to Gravely directly and they gave me the proper spring length. It was way off. IIRK it's supposed to be set at like 12.5" and mine was at 10 something. You may want to check with your dealer or call Gravely to verify the measurement.