Bought core block

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lspann3525

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Removed crankshaft tonight. I will be taking it back to the machine shop. I have a bad feeling he is going to say it cant be repaired
 
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lspann3525

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Took the crankshaft back to the machine shop during my lunch break and showed the guy the scratches and he said they had to already be up there because the scartches have no burr...meaning the scratches had already been polished. He said that it shouldnt effect the rear main seal.
 
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lspann3525

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Got the bottom end almost done just have 1 piston I think I will need to replace because the piston ring top grove doesnt allow the ring to spin almost as if its binding without the ring being compressed. Next question the damaged piston has these numbers on the top "81064G L229 05 411 A3". Ive found a replacement brand new but its for the engine b im not sure which I have I was thinking T. However the part number for the B is 81150B U339 13 307 A3 will this inyerchange?
 

strutaeng

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I guess I missed where you previously mentioned that the piston was damaged? Or you are saying it's damaged because the rings don't spin freely?

Take an old ring and cut off a segment, then use that as a pick to clean out the ring groove. It may just need a file touch up.

Mixing pistons can present a challenge. They need to weigh the same and have the same compression height (also same ring thickness because now make different ones now.) Safest bet is to stick with an original OEM piston if you absolutely need replacement.

Unless it's broken or cracked, I would try to keep that piston. Can you post a photo of it?
 
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lspann3525

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Yes the top ring grove has a scuff around the grove which makes the ring get stuck in the grove. When I dis assembled everything I used a wire brush,brake cleaner and piece of broken ring to clean the groves. All other piston and groves are ok.
 

strutaeng

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Yes the top ring grove has a scuff around the grove which makes the ring get stuck in the grove. When I dis assembled everything I used a wire brush,brake cleaner and piece of broken ring to clean the groves. All other piston and groves are ok.
Ok, understand.

Just file that area then. They make these tiny little cute files. Would be perfect for this, I think. HF has them...

Are you using those special pliers to install them? The ring manufacturers always say not to not "spiral" them on. Admittedly, the oil control rings I do spiral them on, since they are so flexible. But the 2 top rings I use the pliers.
 
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lspann3525

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the grove is damaged. Im thinking this can not be repaired.I'll ask the machine shop this Monday.

The rockauto piston thats 30 bucks is a GM and the pistons in my block are GM just the part numbers are different. I was hoping if someone knew if they would be interchangeable
 

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