Pitting or Casting Defect in Brand new Block normal?

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Intoodeeep

Seaman
Joined
Aug 13, 2011
Messages
64
I have a brand new 1978 Johnson 235 HP Block. It was unused and still in the crate. It was a rare find for sure. While cleaning the block after honing the cylinders I found what looks like a possible casting defect inside the lower exhaust port of cylinder five. Looking at my old block, it looks like there is pitting or casting defects in multiple ports in multiple cylinders. Is this normal to be seen in blocks? Does this need to be fixed/welded or is it fine? They don't look deep but they are there.
 
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emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Would help to see some pictures of the pits. Not sure just where your pits are. The ones of concern are any on the sidewall of the cylinder liner. Small pits probably won't make much difference in the running of the engine. During the combustion process, there is no place for the exhaust/carbon to go-other than out the exhaust. On a used block, it's the elongated gouges (cyl liner scuffing) which will permit carbon/exhaust to migrate up/down the (scuffing slits in a cyl) during each combustion cycle. Over time, that carbon/exhaust can propogate down that tiny gouge/slit to get to the ringsets and cause carbon to accumulate around them. If you are that concerned, you might consider an overbore of .010 to see if the cyl will clean up. If the pits are not on the actual cyl walls- but inside the ports-that's ok. Run it.
 
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