For those that have experience deburring engine blocks, do you recall a brass appearance in the area that was cleaned up on an original cast iron block? Here is a pic of what I’m referring to. I’m not sure if this is a result of a repair or from deburring the block?

Looks like a lot of repair to me. Should be all cast and no brass. What do you mean by original????????????

That appears to have been brazed or welded, likely had some porosity at the parting lines and was brazed/welded to repair.

No telling when it happened, good chance it could be a factory repair.
I’ve seen evidence of arc welding on blocks Known to have never been apart before, but
Not brazing but wouldn’t be surprised. They were cheap back then and didn’t like to scrap
anything questionable….

The block is a standard bore and appears to retain the original paint. My initial thought was a plant repair. I’ve seen blocks that were deburred and washed, but don’t recall ever noticing the brass color, which alarmed me. I figured if the block was recently repaired, it would have been thoroughly cleaned (hot tanked) and there would have been witness of paint flaking at a minimum? However, if it was a post plant repair, maybe the original paint was left to disguise and minimum prep was performed, since it was an internal repair?

That looks like corrosion to me from being ground on and then sitting in a moist climate
try scratching it with a sharp point and see if it is brass or corrosion

Magnet?

Not sure about the corrosion part but can't believe someone would go to that amount of effort to save a block unless it was a BOSS 429 or Lambo etc. No to mention what kind of stress would be required to crack a valley like that? i woul dthink there would be additional damage elsewhere. Do what Cab suggested

i agree with Cab. That's discoloration from rust starting to form where it was touched by a burr tool. Scotch Brite it and see if if shines up.
Doug

Blow the photo up. Looks like a different texture. Poster will have to verify what he is questioning.

That needs a little poking at to determine what the deal is.

But yeah, back in the day, Chrysler hardly scrapped anything; look at all the under- or over-size block dimension stampings for example.
Seems kinda baffling when manufacturing volume & cost-effectiveness are considered, but that's what they did.
Yet they'd ship cars & overnight race parts to their contract racers.
Nowadays, it seems the thinking is 180 degrees opposite.

My first thought is like Cab. Cast iron turns yellow/red as it starts to rust. It just looks discolored where you ran the burr over it. Surely you could tell the difference in the cast iron and the brass when you ran the burr over it? I think it’s just the beginning of rust. Shoot some WD 40 on it.

Did you debur it and is that the only area that looks like that? Does look like a brazed area, but that doesn't explain the look in the area around it, unless that showed up when deburring that area.

what does the outside area look like?

only brass/bronze I see is the bushing for the intermediate shaft.

it does "look" like a repair "braze/weld bead" around the cam bearing area. maybe a stress crack?

but then again I have had a lot of flash rusting while working/grinding/ machining blocks/heads and do have to go back and clean it up. but the cast iron should polish up like chrome and brass should polish up also.


scratching with an AWL is needed and a pic of the outside area of the block.


studying the pic a little while longer it looks like the color (brass/bronze?) is right up to the cam bearing ede. I wounder if it got a gorilla fisted grinder that maybe removed to much of the boss and then brazed/weld to build it back up?

maybe a chunk cracked off when cam bearing were installed at factory and a repair was done? ( you said it looked to be a virgin engine never apart maybe?)

Humm...puzzling indeed!

The ‘stuff’ is down in the lifter bore too so probably contamination of some substance.

I see that now. Appears almost like brazing on the phone screen, looks more like corrosion on the computer screen.

Maybe clean it up in an area or two and see.

can you post a picture showing more of the valley area on that side ?
don't know if that would be beneficial or not to this discussion, but you never know.

I'm going to guess they used a HF Brass burr