340 Id

Casting number on the side will give you the date it was cast.

Look on the front surface of block, just below drivers side head. Should have a series of numbers stamped there. Might look something like this:

EW340P29980006

If it has those numbers, post them up and some one can decode them

Also, be careful if these came out of a twin engine boat. One of them may be reverse rotation. The rear seal knurl is the opposite direction and leaks like crazy when spun normal rotation.

The blocks are the same so that's a good thing, especially FREE!