Almost Perfect Block Okay to Use??

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72DMag

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Received the 5.9 block back from the machine shop. I already the the pistons and rod here and assembled. machinist said the block just neded honed no need to bore it. Well he was almost right or maybe I'm wrong. All cylinders look great but there is one indented scratch on one cylinder and it does catch my finger nail. But it doesn't catch my finger nail all the time and I need to be at an angle for it to catch.

Would this be an issue because the motor is going to see track use? Is there anything I can do to make sure it won't be a problem? I tried a ball hone on it and I'm pretty sure that did nothing. Maybe try a stone honing tool or something? I hate to bore it over because of this especially when it turned out with a super nice cross hatch!

Pics are below you can see that it is a deep mark on the cylinder wall.

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Run it. That's my vote. Doesn't look that bad, seen far worse on non smoker strong runners.
 
@RustyRatRod 5.9 sorry that was my typo and it's been corrected.

@pishta I'm not too concerned if it smokes. More concerned of the moly rings catching it and creating an issue.
 
But I agree, run it. It's in one spot. Might be different if it was a long vertical gash.

Somehow that didn't sound right.
 
If its a scratch, dress the high side with a stone. The ring wont catch on a divot...its an easy test to push the ring pack past it.
 
pishta said:
If its a scratch, dress the high side with a stone. The ring wont catch on a divot...its an easy test to push the ring pack past it.
Click to expand...

If it's been honed over, shouldn't be any high spots, but may be a sharp edge.

I agree, push a ring past it and see if you can feel it with the ring. Probably not. But I might also worry what created the divot. Must have been there before, I'd guess? Or was the engine damaged in any way?
 
If it is high enough in the bore that the rings pass over it, I would be worried the end of the oil ring rail could catch on it. It has two rails to choose from...
 
All of the high compression pressures are on the upper half of the cylinders. Much more critical up there.

Run It . . .
 
What color is the "scratch"? Looks like rust to me, hope it is not. That "scratch" could be a crack. I know it's odd; if it is a crack; that it is horizontal, they normally run vertical.
It's an idea, hope I'm wrong on my "guess", just one more opinion of the many you will receive here.
 
Which cylinder is it (hard for me to tell from the pics), and where is the "scratch" oriented? I'd run it and not worry about it *UNLESS* it's at the front of #1. If it is, be careful- it could be an indication that someone used too long of a timing cover bolt and cracked a cylinder wall.
 
Professor Fate said:
Which cylinder is it (hard for me to tell from the pics), and where is the "scratch" oriented? I'd run it and not worry about it *UNLESS* it's at the front of #1. If it is, be careful- it could be an indication that someone used too long of a timing cover bolt and cracked a cylinder wall.
Click to expand...

I have seen this. And it was midway down the bore of #1.
 
Rebuilt the 5.9 in my durango r/t about 9-10 months ago along with the tranny and transfer case as the durango had 304,987 miles on it. Never been rebuilt and the cylinders were perfect,no ridge and full cross hatch top to bottom..The bearings had 2000 on them as my durango is a 2000.The tranny is why i rebuilt it,the bearing and rings looked good
 
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