6.354 perkins

hi clever fellows,this is my first post,so here goes,i have a 6354 of indeterminate age i think pre 78' as the engine number format is (stamped pos.D on engine)354UR 25707 out of an old bus and turner 5 spd.assuming U for uk built i cant find a year code R hoping some one can help? cheers in advance.

Hey there lad, welcome to the forum. The "R" after the country of manufacture denotes a factory rebuilt engine. The "R" wasn't used in the date codes of engines of that era, I think it was only in the last several years that it has been used.