Loud Knock After Replacing Intake Manifold

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SquareRoot

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Ok guys. I realized I am missing a small nut (maybe 3/16”x1/4”) from my gasket scraper and now, just now after starting the engine a dozen times, I am picking up what sounds like a small bb sound. It’s not synchronous, but random. Take a listen…
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:popcorn:
 

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tdsunderla

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We're invested now, please let us know what you find :)
Will absolutely let everyone know. Going to finish up some other things first like Dakota Digital instrument cluster and Painless wiring harness (items started before changing out the intake manifold). If anyone is close to Melbourne Florida and wants to help diagnose - would welcome a visit.
 

sublimeobs

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@tdsunderla root cause determined yet or still looking?
 

tdsunderla

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Sorry for the delay in posting. I believe I found the culprit (what's left of my razor scrapper nut) in cylinder 6 (see attached photo). Top of piston looks pitted but not destroyed (see attached photo). Cylinder walls and valves look unscathed as well. I am hoping I do not have to replace the piston head.
 

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Ricko1966

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I'd pull that piston,make sure it's not cracked to the ring land and make sure the top ring still floats free in the ring land.
 

HotRodPC

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Sorry for the delay in posting. I believe I found the culprit (what's left of my razor scrapper nut) in cylinder 6 (see attached photo). Top of piston looks pitted but not destroyed (see attached photo). Cylinder walls and valves look unscathed as well. I am hoping I do not have to replace the piston head.
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