Just curious - Could you check for a leak, (while cool) spray soapy water disconnect wire and crank see if you see bubbles? Not sure if it would work, but I think I'd try it if I didn't have access to a scope or before pulling the head.

 

Very creative TSheff. Thats what we do in the A/C field. Soap Bubbles....

 

And the tire world..

 

You would need a mirror on the scope, and scopes are fine for looking for easy stuff, cracks are hard to see even when out.
A leak down/pressure test with the motor warm, and the spray soap and water.
I believe that is how we used to check them back in the sixties at the city service station that I worked at.

 

If you need any help pothole let me know. A younger set of eyes to see something you may not be able to see is always a good idea, lol.

EDIT: I will say this, cracked heads near the spark plug hole is not uncommon.

 

Ohh my, and a young set of eyes is no substitute for an experienced set of eyes,


With a big magnifying glass:-)



.

 

Not my first rodeo with cracked heads, and as a career code welder, I've repaired quite a few. Thanks though.

 

it looks to me to be leaking between the head and the crush washer on the back side of the plug.

 

Pull the plug and clean the area were the plug goes in and get a either get a magnifying glass with a real good light or a real good camera in macro Take a close up and then magnify it. It might show you where your at. As I'm getting older I do that a lot to see the real pita things.

 

It's a really great way to make small things look BIG. I'm a cartridge collector and have to do that with headstamps a lot.