Setting the idle too high can cause dieseling too.
If the cam isn't turning,that would probably make it either a broken cam or a trashed timing gear. well-it COULD be that somehow the timing gear has lost its grip on the end of the cam. Whatever the reason,the front of the engine will need to come apart.
Speed

1954 GMC 350
1957 GMC 1/2 ton
1962 Chevy C-30
1952 Chevy 6400 dump bed project truck
'98 Harley FLSTC
'66 Pontiac Catalina
'76 Chevy 1 ton Duallie
'84 Bronco II
'78 Dodge W-200
'81 Toyota 4X4 truck