If you access the dating records via archive/dating/engine dating/petters as a guest you see the basics only. To see the full images of the original records you must be logged in. In most cases the images add a wealth of interesting detail. Aside from the sale date this will usually include the ID and location of the buyer and details of the engine's/plant's configuration. To be searchable the images have to be indexed, a process by which a human goes through the images and adds to the record of each a selection of data and some key points about the engine/plant. When, after entering the serial you would like dated, you see an entry with a date of xxxxxxxx then you need to follow the request on that screen and ask for the engine to be indexed.