Steering problem
1986 Mercedes Benz 300e 6 cyl Two Wheel Drive Automatic

started experiencing intermitent tumbler lock around sep. of 08. fathers day complete lock up must have key fiddled and wheel strained near 4 hrs. key works with ease at doors and inorder to remove lock retaining ring the key must turn to specific possition . so question, do I shot gun repair the entire lock cyl. grinding off dowl pins or is there a common failure with lock out pin or other . please help an out of work tech. thanks Barry Slater