[HWYSTR455]

Take another pic, zoom in on the knick, at a 45 degree angle, and post please. A close up may be able to tell when it happened, before, during, or after. If the knick isn't protruding into the bore, it was before.

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[72LuxuryLeMansLa.]

Originally Posted by HWYSTR455

Take another pic, zoom in on the knick, at a 45 degree angle, and post please. A close up may be able to tell when it happened, before, during, or after. If the knick isn't protruding into the bore, it was before.

.

I was planning on this. The engine is on the east side of the house so I will wait until evening to get the sun out of the equation. I am also going to use the tripod this time and try a different lens to get some better quality shots from different angles.

Karl

[HWYSTR455]

Cool, I'm curious. I'm starting to lean towards it being there before the machining started. If you can take a ring, start it at the bottom of the bore, and push it up to just under the knick with a piston, that too would give an excellent reference.

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[GOAT WHORE]

Originally Posted by 72LuxuryLeMansLa.

I was planning on this. The engine is on the east side of the house so I will wait until evening to get the sun out of the equation. I am also going to use the tripod this time and try a different lens to get some better quality shots from different angles.

Karl

I have never had luck with my $1000 fancy camera and close ups. I have had great success with my Droid phone camera for close ups.

[lust4speed]

I'm wondering if the mill didn't expose some casting porosity. Take a look at the other two small holes in the photos. Then the question becomes whether the cavity goes all the way through to the water jacket?

[Stuckinda60s]

Originally Posted by lust4speed

I'm wondering if the mill didn't expose some casting porosity. Take a look at the other two small holes in the photos. Then the question becomes whether the cavity goes all the way through to the water jacket?

That would be my guess, also. It looks like a sand hole, similar to the ones by the bolt hole.

[gtofreek]

That's either a casting flaw or it was really rusty around that cylinder at one time. I do not see anyway machining it could have done that. It doesn't even look to be protruding into the cylinder to me. If it is, it would have had to happen after honing. If not, it was probably there for a long time. You cannot go to a 4.150 head gasket because the combustion chamber[of iron heads anyway] width is 4.300". That is why the gaskets are as big as they are. They need to go around the chamber. It should be fine, just deburr it with a fine stone or emery cloth as others have said. I would use emery cloth and my finger to do it. It won't hurt the rings if you deburr it.

[lust4speed]

Here's the same photo enlarged some. The interesting thing here isn't so much the milled surface as the untouched portion of the block in the top part of the photo. Looks like craters on the moon.

[gtofreek]

That moon crater section you speak of is just a protrusion that is at the top of the lifter valley. I can't think of a Pontiac block that didn't have that. It doesn't get decked with the deck surface as it is not level with it.

[lust4speed]

I'm talking about how porous that surface is -- full of pin holes. Guess I could have used a better analogy.

[HWYSTR455]

That's what I was thinking too guys, that it was there all along. Makes me wonder why the machine shop didn't reject it as a candidate for a build/machining. Or at least bring it to the customer's attention.

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[chiphead]

Those are likely casting imperfections, normal deck rust pits and handling dings from moving it around. I've seen so much worse.

You guys are navel-gazing. BUILD IT! :P

[72LuxuryLeMansLa.]

Originally Posted by chiphead

Those are likely casting imperfections, normal deck rust pits and handling dings from moving it around. I've seen so much worse.

You guys are navel-gazing. BUILD IT! :P

By the time it's over I will have $9,000.00 in this engine, not including the precision measuring tools that I will have to buy to assemble it. Naval gazing.... I think not! More like I will not settle for "ehhh, close enough! I need to know if this will cause trouble! If this allows a spot to get red or white hot during combustion and then ignites the A/F mixture while the piston is still traveling towards TDC ....... I'll be naval gazing on the side of the road waiting for a tow truck!
If smoothing so called sharp edges on pistons is a concern, how would the sharp edges of this damage or imperfection, if that is what it is, not be of concern?

Karl

[HWYSTR455]

Originally Posted by chiphead

Those are likely casting imperfections, normal deck rust pits and handling dings from moving it around. I've seen so much worse.

You guys are navel-gazing. BUILD IT! :P

I think as long as there's nothing protruding into the cyl bore, it should be fine. Would be nice to see where the fire ring will lay, and the depth of the stuff on the deck itself though. And would still recommend putting a straight edge on there.

The area that is in the bore is above the ring pack, so it most likely will just fill with carbon after some run time anyway.

(Dang, thought I hit 'submit' already!)

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[72LuxuryLeMansLa.]

Originally Posted by GOAT WHORE

I have never had luck with my $1000 fancy camera and close ups. I have had great success with my Droid phone camera for close ups.

The only times I've had problems getting good shots with my Olympus E-1 was when there was a problem with operator head-space and timing. This camera uses ZUIKO DIGITAL lenses that produce exceptional colors and crisp images. I am going to post additional images but I wont be able to get to it before Friday. The tripod is mandatory for a shot like this especially if you shake like I do.

Karl

[GOAT WHORE]

Originally Posted by 72LuxuryLeMansLa.

The only times I've had problems getting good shots with my Olympus E-1 was when there was a problem with operator head-space and timing. This camera uses ZUIKO DIGITAL lenses that produce exceptional colors and crisp images. I am going to post additional images but I wont be able to get to it before Friday. The tripod is mandatory for a shot like this especially if you shake like I do.

Karl

That's my point, it can be very hard/complicated. Have you tried a newer smart phone? Blows me away how easy and what a great micro shot my Droid takes.

[72LuxuryLeMansLa.]

Originally Posted by GOAT WHORE

That's my point, it can be very hard/complicated. Have you tried a newer smart phone? Blows me away how easy and what a great micro shot my Droid takes.

No I have not.... I use a $35 walmart flip phone..... Talk only, I don't even like to text

Karl

[GOAT WHORE]

Originally Posted by 72LuxuryLeMansLa.

No I have not.... I use a $35 walmart flip phone..... Talk only, I don't even like to text

Karl

Oh ya, forget that then lol. Man you must have a desk job or something to be around a computer all day. I do 90% of my PY board talk from my phone.

[chiphead]

I'm not being flip in my response. I don't care if it's a 500 beater or a high dollar engine, I take the same care in prep and assembly.

Like was said, put a straight edge across it and see how deep the mark on the deck surface is. How deep is it? Can you catch your finger on it? Put some 400-600 grit on a flat sanding block and make a couple of passes over the area and see how it cleans up. Then lay the head gasket over it and see where the fire ring lands. Those 1016s will seal almost anything within reason. I used them on a 350 that had a really pitted and dirty deck surface and they sealed fine.

As for the mark on the lip of the cylinder, just smooth it over. That'll allow ring installation and prevent any possible hot spot. I assume the block was magnafluxed so any crack should have shown up. Which means the cylinder nick is superficial.

[72LuxuryLeMansLa.]

Originally Posted by HWYSTR455

Take another pic, zoom in on the knick, at a 45 degree angle, and post please. A close up may be able to tell when it happened, before, during, or after. If the knick isn't protruding into the bore, it was before.

.

These pics may be a bit better....

Karl