You may have to pull the valve cover to see them if they are there.
Good reading on the Hoffman Site about the crack repair.
https://newsite.hamheads.com/porsche/alt-m96/m9697-986996-crack-repair/
Here's a snippet.
"—Some radiate from one of the coolant expansion plugs over toward the nearest spark plug well.
-Others migrate from a valve guide bore across the machined spring well and end at the nearest spark plug well.
–Most cracks occur on the outer cylinder positions, but on occasion the center cylinder produce a crack that runs from a spark plug well across an exhaust spring well and end in a valve guide bore.
—Occasionally the plug well to spring well crack will continue from the spring well****on to the nearest head bolt bore. These are the worst examples, but we can repair them too.
–Most of the cracks that gravitate toward a valve guide bore head toward an exhaust guide. However, the 3.4 heads that have just 2 coolant expansion plugs beneath the lifter housing will sometimes crack from a spark plug well to an intake guide bore. I have not yet seen this on a 3 expansion plug head.
With over 25 years of cast aluminum crack repair to draw upon I have developed routine repairs for every type of crack that we see with these heads.********The type that run into a guide bore are much more involved than the type that don’t and are therefore more expensive to repair. ****
Crack repair requires a ****very****specific series of processes to end up with a reliable repair. And the cracks that run through the valve guide area are the most demanding. ****Even shops that say they can repair cracks will often shy away from these challenging repairs, or worse do a poor “repair” that will get through the warranty period but fail down the road."
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