locked up engine
 

ust by chance there isnt any odd thing like starter stuck or something that would lock up engine, short of siezed from no oil or something!!!!

You didn't mention what model.....what are the circumstances just all of a sudden or was it running? Gas, Diesel...etc

could be other things
 

including a stuck cam if ran low on oil. bottom end could be ok and cam stuck. just do basic checking to determine where the stickage is.

tom w

Hydraulic lock in a cylinder or cylinders. Try turning it backwards. If it goes, then remove the glow plugs and turn it forward. Another option is a valve failure, whereby the head of the valve has separated from the valve stem, and the pieces are buried in the top of the piston.