Crack are what????

[Dave Koehler]

Machine shop told me it was just a scratch

But was it magnafluxed?.
Did they see it first hand or just your pictures?

[MotionMachine]

"Had a guy bring back a block because it had a crack right in the side. Luckily it wiped off, since it was just a string of permatex sealant.
At least that did look like a crack."

Similar thing happened to me once. 2 geniuses called back all pissed off because the 396 block I just bored had cracks in all the cylinders. So I drive to their dirt floor shop, which by this time had assembled all the locals to lynch the "new guy" in town. Yup, every cylinder had a line the entire length of the bore from where I measured each one with a bore gage. It still took some convincing before they believed it. So glad I'm at the point in my career where I pick the customers, not the other way around.

As far as those cracks go, I've magged a lot of cranks and other than that small section in the radius, I've never seen cracks act like that. The only time I've seen anything similar was on a welded journal. But even then, the cracks were more in line with the direction of rotation between beads of weld.

[Dave Koehler]

Similar thing happened to me once. 2 geniuses called back all pissed off because the 396 block I just bored had cracks in all the cylinders. So I drive to their dirt floor shop, which by this time had assembled all the locals to lynch the "new guy" in town. Yup, every cylinder had a line the entire length of the bore from where I measured each one with a bore gage. It still took some convincing before they believed it. So glad I'm at the point in my career where I pick the customers, not the other way around.

As far a

Chuckle
I had a CAT mechanic pull that on me on a 3208 job. Fresh out of CAT school and knew everything about everything.
Brought in the official CAT manual with Sunnen specs, blah, blah.
Not my first 3208 BTW.
Even after I showed him where that mark came from he was still aggressively insistent that it would affect ring seal and his future pension.
Fine, I will make it all better. Come back in an hour.
1 swipe down and up and it magically disappeared.
He walked off satisfied he had won the war.
I continued to do that after final measuring from then on with all blocks just to avoid any future stupid is encounters.

[1972ho]

It don’t crack no more just to show you it wasn’t a crack the picture is after machining

[TMSJoe]

I too have noticed the carbide ball from the Sunnen bore mic leaves and unsightly mark. I had a Harley guy believe it was a crack. I woofed it with the hone and it was gone. After that I hone to size, let it cool, measure, and last I give it a quick swipe. That was probably 30 years ago. Now that I think of it. It must have been last week because no way I've been doing this that long!

Similar thing happened to me once. 2 geniuses called back all pissed off because the 396 block I just bored had cracks in all the cylinders. So I drive to their dirt floor shop, which by this time had assembled all the locals to lynch the "new guy" in town. Yup, every cylinder had a line the entire length of the bore from where I measured each one with a bore gage. It still took some convincing before they believed it. So glad I'm at the point in my career where I pick the customers, not the other way around.

As far a

Chuckle
I had a CAT mechanic pull that on me on a 3208 job. Fresh out of CAT school and knew everything about everything.
Brought in the official CAT manual with Sunnen specs, blah, blah.
Not my first 3208 BTW.
Even after I showed him where that mark came from he was still aggressively insistent that it would affect ring seal and his future pension.
Fine, I will make it all better. Come back in an hour.
1 swipe down and up and it magically disappeared.
He walked off satisfied he had won the war.
I continued to do that after final measuring from then on with all blocks just to avoid any future stupid is encounters.

[modok]

I usually measure at 45 degrees, for whatever reason.... they usually don't look there.