Author Topic: Advice? Tight pistons on rebuild  (Read 1045 times)

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SandwichEnthusiast

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Advice? Tight pistons on rebuild
« on: April 23, 2010, 08:49:47 AM »
Can I get some advice?

So, I just put the cylinders on the pistons today after having the cylinder bored and honed to .25 oversize: new pistons new rings new pins new clips.
I cleaned the honing compound off real well, blew it dry, oiled up the walls, was really careful about the ring gap etc.
And I feel like it's turning over really tight: I can turn the rotor with some effort, and there is some noise, but it isn't scratching the cylinder walls or getting caught.

(video if anyone's interested)
http://www.uoguelph.ca/~ibaran/ian%20motor%20002.avi

SO, how tight is too tight? Is my engine going to seize on startup? I don't know anything about anything, so I have nothing to compare it to.

Thanks a lot,

Ian

Offline Old Scrambler

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Re: Advice? Tight pistons on rebuild
« Reply #1 on: April 23, 2010, 08:57:30 AM »
Hopefully you sent the pistons and rings along to the shop for the re-bore so they could match them. When they were returned each piston should be marked to match the barrel number.

The rings will fit snuggly against the wall and at TDC will be somewhat compressed = pressure!
Dennis in Wisconsin
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Offline bucky katt

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Re: Advice? Tight pistons on rebuild
« Reply #2 on: April 23, 2010, 09:19:59 AM »
are there sparkplugs in the head yet?
Of all God's creatures there is only one that cannot be made the slave of the lash. That one is the cat. If man could be crossed with the cat it would improve man, but it would deteriorate the cat.
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SandwichEnthusiast

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Re: Advice? Tight pistons on rebuild
« Reply #3 on: April 23, 2010, 09:32:37 AM »
No, I'm still putting it back together, the cylinder head is off, I just put the cylinder back on.