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piston autopsy case #1

Definitive Dave

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I am pretty confident I know what killed this piston, just thought i would post pics for confirmation.
Background: eBay customer ran for a month and then locked up, cylinder kit has already been replaced and I will get around to contacting the vendor soon.

The Carnage -
IMG_9842.JPG IMG_9843.JPG IMG_9844.JPG IMG_9845.JPG IMG_9846.JPG
 

cus_deluxe

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if the wrist pin bearing is intact i would say it snagged a ring.
 

Definitive Dave

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I saw it differently and that's why i like threads like this.
To me it looks like the soft steel circlip got loose or perhaps the end came off and it got above the piston and crushed the ring land.
In the last three pics i see an indentation in the cylinder roof and the piston crown, that both look like small piece of wire, rather than a piece of ring.
Am i crazy?
the next one will be even more odd :)
Dave
 

Wonkydonkey

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I saw it differently and that's why i like threads like this.
To me it looks like the soft steel circlip got loose or perhaps the end came off and it got above the piston and crushed the ring land.
In the last three pics i see an indentation in the cylinder roof and the piston crown, that both look like small piece of wire, rather than a piece of ring.
Am i crazy?
the next one will be even more odd :)
Dave


That is what I thought wrist pin clip,, came out and popped around broke the piston an then bits helped break the piston a bit more. But upon taking apart, was the clip aaywhere to be seen ? IE still at home ?

Edit; looking at the second lot of pics, I still guess wrist pin clip was the culprit of the start of the carnage
 
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