Piston land keyway?

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jimjumper
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Piston land keyway?

Postby jimjumper » Sun Mar 15, 2020 2:29 pm

Finally got the head clean and ready to re-install. Pulled the pistons this morning and, as expected, the top rings on both pistons were in pieces. One cylinder even had a cracked second ring. I assume that cleaning the pistons and checking their specs is next but when I was pulling the pieces of the ring out of the piston land I found what appears to an alignment keyway? Or is it just a really stuck piece of the ring? It is only there on one piston. I'd post pics but it is really small.

winston
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Re: Piston land keyway?

Postby winston » Sun Mar 15, 2020 3:34 pm

Sounds like starter fluid has been used in the past. I don't think there is any kind of keyway in the pistons. Make sure the lands aren't broken. If the rings are it would sure be possible the lands are too.

jimjumper
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Re: Piston land keyway?

Postby jimjumper » Sun Mar 15, 2020 6:56 pm

You were correct. After your reply I went at it a little more aggressively and it popped off. First time doing any of this so I am being ultra cautious and slow. Good news is the piston look great! And yes, the previous owner did use starter fluid on more than one occasion. After almost rolling it in a ditch one day she parked it and walked away. 4 years later, I asked about it and she told me if I could get it started, I could have it! Thanks for the reply, I doubt this will be the last stupid question I have before it runs again!

winston
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Posts: 5300
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Piston land keyway?

Postby winston » Mon Mar 16, 2020 6:45 am

Make sure you check ring to groove side clearance when you get your new rings. Top ring should be .0031 - .0045", 2nd,3rd, and bottom should be .0008 - .0022".


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