W2 coolant leak

Where exactly is the leak?
On the quick I’d say some welding would work since it’s cast iron but this may be an over simplification.
I believe under the valve seats. It did it last year and my machinist had it welded and put new seats in. I’ve pulled it 5 times this year and it did it again. Pretty sure it filled a cylinder this time and broke a rod. I’m going to start tearing it down tonight