I have a 413 shortblock with a casting # of 2658836, 4.180" bore, it is turquoise color, has the unique ribs on the side of the block, steel crank with 8 bolt flange, holes ARE tapped on the flange, no centering ring on the flange, all my research says the 8 bolt flanges have un-tapped holes? But what puzzles me the most is there is no casting date on the block, only the casting number mentioned above, number 6 cast into the block in a few places, but no D/N shift indicator and no date, id pad is blank as well, just trying to figure out what year this is, also has 1851535 std RB rods, dished pistons and a gear drive gear on the crank, cam gear is missing. Anybody an expert on 413 industrial/HD truck engines?
I'm no expert on those motors but my volume #1 casting book shows that casting number as a 426 industrial block with no casting date codes
The tapped crankshaft tells me it is a later, after 1962 RB industrial crankshaft, maybe a marine motor to start with
IHTHs
