Cylinder bore is scratched up!

[Swinger 340]

I got a couple more pics. Water sat in there for sure, the lines are horizontal to the ground. It definitely is acidic damage to the bore, it’s pitted. Everything else looks good as far as I can tell. Didn’t pull the pan yet.
The 70k engine plan (A) was reseal and convert to carb and roll by late May. The reason I paid $800 was for the millage, 1 owner, garage kept, synthetic oil for it’s life, show truck. I would have never bought it if I knew the cylinder bore was roasted. If you saw my cam thread you know I’m already at the edge of my ability.
I’m not sure how I will go forward, or if I can. Any ideas, input, and experiences are greatly appreciated. My first idea is find another short block, in terms of the cheapest resolve.
I’m also curious how it would run if I smoothed it out slightly, and what the repercussions are. I actually don’t like that idea, and I am very much the opposite of half assing anything, but money is a thing here. On the bright side, you guys are responding to my whoas and that’s fcking awesome. Big thanks! Wish I could return the favor lols.
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If you are looking for the cheap way out, I would clean up the walls the best I could and then at different heights of the piston, add Marvel Mystery Oil and see if it falls into the oil pan. If it does, I would pull the piston and check the rings for corrosion and possible removing them to clean. Do the first test again. I have ran my first 340 with a wrist pin broken and the pin sliding on the cylinder wall, which put a 1/8 inch gouge into it. Ran for 10 years that way, until I found another motor to replace it.

 

[BillGrissom]

$200 doesn't sound bad for the other good parts, such as the crankshaft and heads. For comparison, look at the cost of even simple parts for ex. a newish Audi, like $2K for one matrix LED headlamp.

 

[mayhem]

To the OP, lean into abodyjoe's block & pistons - he's more than reputable and you can trust his stuff is right. Use what you can from the $800 (now $200) boat anchor but save yourself more potential headaches and do not reuse bearings - they're inexpensive/cheap insurance compared to the damage sticking the old ones into the new block could cause.

 

[Woody500]

In the Mid-to late 80s I bought a 1956 Higgins 17' Speedster Utility that someone had repowered with a 225CI Marine Slant Six. It hadn't been winterized and the Cylinder head was externally cracked, and luckily the only cracked part. But it was stuck!
So I poured penetrating oil(probably the original K'nocker Loose back then, not the crappy PB Blaster clone they sell now) and took off head & cyl 3 rusty. So I cut down a 4x4 till it barely fit in bore and wailed on it till the piston moved & then moved slightly back and forth with big socket, just a little bit.
Then I used 80 Grit sandpaper(cheep ****) & sanded the rust off & vacuumed. Then I turned engine until I could see where rings sat & wiped & sanded that too. Then move up a bit & back down & wipe, multiple times.
Then clear to top backing down & oiling/wiping as I went. Left it @ top & did again later, basically got as much cleaned as possible
I then reassembled with junkyard head from Wrecks Inc & we Slalom Skied with it for several years. Higgins has smallest wake EVER. Great boat!
AND IT NEVER SMOKED! EVER!
Let the bitching begin!

 

[RustyRatRod]

In the Mid-to late 80s I bought a 1956 Higgins 17' Speedster Utility that someone had repowered with a 225CI Marine Slant Six. It hadn't been winterized and the Cylinder head was externally cracked, and luckily the only cracked part. But it was stuck!
So I poured penetrating oil(probably the original K'nocker Loose back then, not the crappy PB Blaster clone they sell now) and took off head & cyl 3 rusty. So I cut down a 4x4 till it barely fit in bore and wailed on it till the piston moved & then moved slightly back and forth with big socket, just a little bit.
Then I used 80 Grit sandpaper(cheep ****) & sanded the rust off & vacuumed. Then I turned engine until I could see where rings sat & wiped & sanded that too. Then move up a bit & back down & wipe, multiple times.
Then clear to top backing down & oiling/wiping as I went. Left it @ top & did again later, basically got as much cleaned as possible
I then reassembled with junkyard head from Wrecks Inc & we Slalom Skied with it for several years. Higgins has smallest wake EVER. Great boat!
AND IT NEVER SMOKED! EVER!
Let the bitching begin!

You purt near bout caint kill a slant 6. Something about them just wants to run.

 

[Woody500]

You purt near bout caint kill a slant 6. Something about them just wants to run.

Always have said it proved Chryslers' Engineering & Metallurgy is superior.

 

[Woody500]

Only Slant I ever owned was in a parts 65 Cuda I had. It had been run out of oil and locked up. And Then the crankshaft front bolt had been sheared off!
What size is that thread? WOW!

Always have said it proved Chryslers' Engineering & Metallurgy is superior.