BIG piston deck clearance issue

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dstan

dstan

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So I began to clean the second hand 383 that I bought to do a cheap rebuild on and put in my truck. I began cleaning the pistons and numbering them and when I got to the second to last piston I found that it sits WELL above 0 deck. The deck seems level and every other piston is perfectly at 0 deck. Anyone know what could cause this or what to do? I'm thinking maybe just replace that piston and rod.

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Did you get drunk and put both bearings on the rod side? Sorry, that's the only possible explanation I can produce on such short notice.
 
Leadfoot said:
Did you get drunk and put both bearings on the rod side? Sorry, that's the only possible explanation I can produce on such short notice.
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I haven't taken it appart yet. It was suposed to be running when pulled.
 
I'd be pulling that piston and rod and doing some inspection and measuring.
That would be a WTF? moment for sure.
 
TrailBeast said:
I'd be pulling that piston and rod and doing some inspection and measuring.
That would be a WTF? moment for sure.
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I'm pulling them all. I was numbering them to get them back where they go. I need to rehone the cylinders either way.
 
How did the other piston look that's attached to the same rod journal?
 
RustyRatRod said:
How did the other piston look that's attached to the same rod journal?
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All of the others were perfectly 0 decked. My first thought was a possible bent crank, but then I realized that that is the only one that isn't perfect.
 
dstan said:
All of the others were perfectly 0 decked. My first thought was a possible bent crank, but then I realized that that is the only one that isn't perfect.
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Then I would suspect a different (incorrect) replacement piston. Measuring the compression height will verify that.
 
Did it come with heads? Look to see if damage was inflicted to the head on that cylinder.
 
tonysrt said:
Did it come with heads? Look to see if damage was inflicted to the head on that cylinder.
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It did come with heads. They look fine and there are no valve marks on the piston. I'll pull it first to see it may have spun a bearing resulting in both the bearings somehow being on one side.
 
dstan said:
Don't get hostile.
I am just saying that they aren't a mismatched set of pistons.
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Hostile? Now that's funny. No,you don't know if they are mismatched or not. You don't know, because you have not verified. That's what I am trying to tell you to do.
 
GeorgeH said:
rolled and stacked bearing.
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It's possible. Haven't seen that but once since 1974. Also possible is that the rod nuts have backed off. He will simply not know without verification.
 
Let me guess! the intake valve didn't open and the vacuum stretched the rod. It's possible:rofl:
 
dstan said:
So I began to clean the second hand 383 that I bought to do a cheap rebuild on and put in my truck. I began cleaning the pistons and numbering them and when I got to the second to last piston I found that it sits WELL above 0 deck. The deck seems level and every other piston is perfectly at 0 deck. Anyone know what could cause this or what to do? I'm thinking maybe just replace that piston and rod.

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I I had that engine in my shop I'd be able to tell you what the problem is. Since you have the engine in your shop maybe you can tell us why the one piston is sticking out of the block?
 
AndyF said:
I I had that engine in my shop I'd be able to tell you what the problem is. Since you have the engine in your shop maybe you can tell us why the one piston is sticking out of the block?[/QUOTE

Well now I feel like an idiot. :realcrazy:

Just pulled the oil pan to get that rod out and foud that the cap had about a 1/4' on play where the po must have tried to pull it at some point.
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AndyF said:
I I had that engine in my shop I'd be able to tell you what the problem is. Since you have the engine in your shop maybe you can tell us why the one piston is sticking out of the block?
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Well now I feel like an idiot. :realcrazy:

Just pulled the oil pan to get that rod out and foud that the cap had about a 1/4' on play where the po must have tried to pull it at some point.
 
The joys and mystery of opening up a used engine that's been sitting for who knows how long for what reason.
 
ragtopfury said:
The joys and mystery of opening up a used engine that's been sitting for who knows how long for what reason.
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Well ur either going to crank grinder or buying a diff. crank, might as well stroke it !!
 
If the crank is not hurt than just polish it and use it! unless you want a stroker, You can't fix it unless you know what is wrong.
 
ragtopfury said:
The joys and mystery of opening up a used engine that's been sitting for who knows how long for what reason.
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brian6pac said:
If the crank is not hurt than just polish it and use it! unless you want a stroker, You can't fix it unless you know what is wrong.
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The crank seems perfeclty smooth and the bearings show almost no wear (I'm still replacing them). I might get a set of aluminum heads, but don't plan on stroking this one.
 
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