My Craftsmen Self Propelled is not working

[ash2junk]

My craftmen Lawn mower is working fine except the self propelled part. The string which is used to pull the propelled is not going back to its original position and even if I hold it during mowing it doesn't work. This is one year old lawn mower with the Craftsman Platinum 190cc 22" Briggs & Stratton Rear Bag Rear Propelled Lawn Mower Model# 37435. Any suggestion is appreciated. Thank you

 

[SONOFADOCKER]

Have you looked to see if the small runner drive belt has snapped or come off the pulley ? You can see it if you tilt the mower backwards - handles touch the ground .

 

[SONOFADOCKER]

Also that area gets packed with dead grass clippings

 

[benski]

Also that area gets packed with dead grass clippings

In addition to the grass clippings packing in, it's not unusual to have the wheels bind up with tall grass shoots between the axle and wheel.