Blocked off coolant port above serial number?

Just took of the head to replace the head gasket. When i got the head off i noticed a “pile” off gunk setting on the head gasket just above the serial number. The head has a coolant port in that location but the gasket and the block does not and it is visible in the block that the port was once there. Does anybody know the reason for this?
 
If it is the one I am thinking of ....

Actually there is a large oblong passage way between the head and the block which was added in October of 28 or 29 for additional cooling.
 
Last edited:
I've attached a photo of a head with the hole you're talking about circled. It's true that there's no corresponding hole in the gasket or the block there, and gunk does tend to accumulate. I don't know why this hole is in the heads, but it's in all of them, even aftermarket HC heads.
 

Attachments

  • Screen Shot 2020-12-04 at 11.29.55 AM.jpg
    Screen Shot 2020-12-04 at 11.29.55 AM.jpg
    19.5 KB · Views: 93
Actually there is a large oblong passage way between the head and the block which was added in October of 28 or 29 for additional cooling.

You can see in the attached service bulletin that this is a different passage than the one he's referring to. You can also see that the passage he's talking about is present on the head but not on the gasket. It's the only one that doesn't match. Very weird.
 

Attachments

  • Screen Shot 2020-12-04 at 11.42.38 AM.jpg
    Screen Shot 2020-12-04 at 11.42.38 AM.jpg
    16.2 KB · Views: 99
The hole circled is the hole i was referring. I tried to upload a picture with original post but it didnt work. Thanks for the thoughts! Wasnt sure if i had a mismatch of some sort.
 
Back
Top