(TL;DR debrief) Well, Imma have a snickers....

[hindsight2020]

The power of conversation. I was able to clarify the mechanic's position today. It appears a case of a simple misunderstanding of "required vs desired".

Where we got off the rail a bit initially was in the hesitancy to pull the cylinder, which puzzled me without context. After further consultation it does appear there's nothing to gain regarding the items of interest I was actually concerned about (any rotating internals being bent/broken tweaked). Compression checked, continuity on all moving pieces checked, and TDC verification was accomplished, the engine appears straight.

The hydrolock theory was talked about briefly and quickly ruled out based on the aforementioned evidence and what he observed when he pulled the plugs. There was no river of fluid when he pulled them, nor was the top plug oil fouled.

So now we wait for the engine shop quotes before proceeding. Based on my educated presumption of big item integrity, I'm going the IRAN route, and try to keep the airplane flying. Replacement of all studs and thrus, NDI/recertification (and repair if needed) of the case, inspection of the affected cylinder and repair as necessary, freshening up of the internal bottom end wear items, and bolt it back together. I'll try to keep the thread updated.

 

[Omalley1537]

Seems like a theory of case contamination without any evidence thereof.
I'd replace the studs, scope the cylinder, check the oil screen and absent negative findings fly on.

My only concern with that route is that if I’m not mistaken, the through-studs also supply the clamping force for at least one main bearing…meaning the engine could’ve been running with a bearing that didn’t have adequate retention and may have rotated some (or is about to).

 

[masloki]

How was the snickers?

 

[hindsight2020]

How was the snickers?

Rather sour turns out.

Month and half story condensed for the TL;DR crowd: vendors balked at the request for IRAN, every single one of them upsold me into overhaul. Overhaul quotes were of course as would be expected of this post-covidian, money printer go brrrrrr clown country. Inflation ran away from my entry point of participation, and with no insurance claimable event to inflation-adjust with (that's really what killed it), game over.

If it had been a forever airplane, perhaps throwing good money after bad would have been no problem. But it isn't, so I won't.

Not the ending I expected for this decade long ownership chapter. Win some lose some. Slowly researching loss-cutting options. I'll be taking a break from this crap and forget about things for a while. I want to be present for my family during the holidays, my frustrations with the hobby have frankly been getting in the way of that for the past couple months.

All that said, I'll probably be back to ownership at some point in the future. Should be no surprise to anyone what the offerings I'll be focusing on going forward. Until then...