I have a older magna tillsmth rear tine tilller. The worm gear is worn out by some moron who engeged the tine with all there body weight on it . I have researched this tiller alot . I found out that MTD was the last owner of this model ,and they have no info on this tiller .The john deere corp had this model for a short time I did get a manual off of ebay but they as well dont have any parts or they are discoutinued . I would appreciate any help in fixing this tiller the modle number is 500810 - 343 -1031 thanks 12027boatman