Cracked Block Help

Those plugs in the block are for cleaning the core sand out at the foundry, they are not there to prevent cracks from freezing.

 

The GM block serial number is right front just above the waterpump mounting boss where it protudes to make up for the left bank forward block design

 

The only numbers i can find on the block are the ones i posted previously which were all on a single sticker. Other than that this is all I can see.

 

What you are showing me is the CASTING numbers. That's the numbers that tell you what plant,what time and what day it was cast. The numbers that you need are STAMPED in the cylinder head mounting on the back of the block. Here is a web site that explains the stamping numbers. http://www.nastyz28.com/sbchevy/sblock.php

 

ah, well that explains why I couldn't find it. Thanks

 

I really hope I helped you.

 

try here
http://www.marinemechanic.com/merc/distributors/mercurymarine/sterndrive/gmblockcodes1.PDF

If there is an issue where Merc needs to identify which GM engine it is, this is where they always look.
PS remember if you see references to left hand engines that means standard rotation as marine engines are viewed from the flywheel not the balancer end like automotive guys use