TOPIC: no serial # on block

I have a 76 mercury 1500 and it was supposed to have been rebuilt, but I noticed there is no serial number on the block. I am looking by the fuel pump that are by the intake port covers. I do have a serial # on the transom clamp. The other inline 6s have one on the block too. Can any one shed some light on this?

look around the starter mount bracket some mercs had them there.

If you have found the raised boss near the casting number aft of the transfer port covers and there is no number stamped - it is probably a replacement block.

I checked, there is a raised block but no numbers. I was hoping to determine it was a 1500 and not a 1150. Any way to tell with out tearing it all down?

Take a transfer port cover off the intake side. Then take a picture. The porting is a bit different between a 1150 and a 1500 from that year. Not sure but the piston may not have a power port hole if its a 1150 .
Conrad

If you decide to remove a transfer port cover - it is possible that someone has put replacement pistons with power ports in an 1150, so you would need to rotate the crankshaft to where a piston visible with the transfer port cover off is up on its stroke.
Then reach in and up the cylinder wall directly in line with the intake ports and as if you were trying to reach the intake ports.
A 1500 will have a boost port relief machined into the cylinder wall.
The 1150 (up to about '84ish) will not have a boost port.
See attached picture.

An easier alternative is the see which carburetors are installed and take a peek at the main jet to see what size it is.
I'm not sure of all the carbs found on a 1500, but a couple were WMK-11 and WMK-14.
The jets installed should be .080 or .082 on a 1500.
Thom

I think it was a replacement power head and not a rebuild. It's gonna be a bit till I get a chance to look at it again and really tear into it. Thanks for all the help so far.