Many thanks to all.
Oh well, I was really hoping for a location of a big sticker on the engine saying its horsepower...

I have a 240d, made in 1978, registered in 79 wich was bought second? hand with a 616 engine of unknown heritage in it. I also have another engine, reconditioned which is supposed to be a 240d engine but (i have not seen it yet) apparently has the air intake coming over the top or something....

I intend to install the 2nd engine as soon as the first one goes (idling problems, smoke...great ones it gets going on a motorway, no apparent loss of power) and was trying to find out whether the 2nd engine was the most powerfull one or the original 65 Hp one.

Having run out of diesel lately, due to a faulty gauge, I know that the diesel pump on the current engine has some sort of plastic circular, white top, pump that you unscrew with your hands to pump the air out, but that migh be a later addition.

I will check for the things that were pointed out.
Again, many thanks.