My bad, they are studs. Although I can't prove anything, I am thinking it's the cap bolts which are letting loose rather than the cap breaking, so I'm hoping different bolts or studs will prevent this issue.
whats the breaks look like? witch ones got polished more? does it look like the bolts let loose first?
Cap pieces got bounced around in the block, so it's hard to tell on them, but they had an uneven break as I'd expect from cast. The cap part of the bolts must have exited via the hole, the bolt parts in the block were clean breaks, although I haven't really examined them closely. Thinking about it, with good bearing clearances the force should be spread across the caps fairly evenly
Fortunately, It looks like the block hole can be patched easily. If I were to weld it I would get a nickel electrode. On an old Kohler, I bolted a plate over the hole using JB weld as a sealant. Just to keep the oil from splashing out, nothing structural. BTW the word you're looking for is phooey.
NO, NO, NO............not phooey! F>I>N>E as in fust-rated, in-secure, new-rotic, emo-ville...........lke in Italian Job.
Chewey gumm and Hair Spray fix ? No?
Jimfoo, this is exactly the same thing that happened to me. I just came across this thread and when I saw the picture I thought it was my main cap!
It must be a fault in the casting because I also broke the number 2 cap and it was the second time that I've seen this.