Bruce Butler Wrote:
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> HUTCH 7.62 Wrote:
> --------------------------------------------------
> -----
> >
> > The EMD 567-c primemovers on SP's GP and SD 9's
> > were modifyied to use 645 power assemblies
>
> Hutch
>
> 645 power packs in a 567-C block has been a common
> practice for quite a few years now. It
> facilitates simplification of the parts inventory
> among other things. The 645 has a 1" bigger bore
> than the 567, but the stroke is the same. EMD
> accomplished this by making the walls of the liner
> thinner such that the outside diameter of the
> liner is the same for both. The 710 engine has
> the same bore as the 645 but a 1" longer stroke;
> thus 710 liners cannot be used in a 645.
>
> I don't think 645 liners can be put into a 567-B
> block, but I think they can go into a "BC"
> converted engine. I think that the major
> differences between a "B" and a "BC" are in the
> cylinder head but I am not sure whether a "BC"
> cylinder head is interchangeable with a 567-C (or
> a 645) cylinder head.
>
> Maybe some folks with more mechanical knowledge
> can offer more details about the "B" to "BC"
> conversion.
>
> Below is a picture of ex SP 3194. This was a
> passenger GP9 and still carries it's boiler in the
> short hood. Notice that it has dynamic brakes and
> the smaller fuel & water tanks with the air
> reservoirs behind the tanks. This unit now
> belongs to the Golden Gate Railroad Museum and
> lives with the rest of their collection at Niles
> Canyon. This picture was taken 9/2/2005 at
> Hunter's Point.
>
> [i1167.photobucket.com]
> M/HPIM0295_zps4f3ea7a3.jpg

You want A C or newer block with 645 powerpacks as EMD no longer supports the 567 block anymore.