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Discussion Starter #1 (Edited)
Hi im new here, im not gay.. My problem is

1, I had timing chain come off, and notice my rockers were broke on my valves,, so i took off the cylinder head cover off and notice one of the valves snapped off and left a chip in the center of the piston head about 1/4" deep/wide,, which also damaged the head cover,,

im getting a used cylinder head from a junk yard.

and new chain, etc

will my piston be ok with a small knick in it?

oh its a 2007 2.2 ecotech
If not how complicated is it to replace it in the position im in now..

I cant sand it down its a lil to deep i think

thanks
 

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It could be fine but it's cheap and easy enough to replace the piston, don't even have to pull the engine out to do it. As long as the cylinder is fine then put in a new piston and new head and call it a day. Rod bolts are torque to yield though so make sure you replace those too
 

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Discussion Starter #3
ok thanks, so i need to remove the oil pan to remove the pistons is this correct?

and do i need any special tools to replace these? are used pistons with rods connected ok to use or do i need new?
 

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Assuming you aren't going to be adding a supercharger or turbo to it then a used stock rod and piston would be just fine. Only special tool you need is a ring compressor but even those are pretty cheap. And yes, you have to remove the oil pan to swap it out
 

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Discussion Starter #6 (Edited)
ok, hopefully last question but probably not,

I see on ebay they sell new piston heads, would these have rings already installed??

or if I bought a used one is replacing the rings necessary?

and on the youtube videos they say it needs rehoned is this so?
 

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If your rod is good I would just replace the piston and rings, this way your rod bearing will match the crank. Mark it when you remove it so you don't change it orientation even though I think they only go in one way. Honing is only necessary if you have a ring ridge at the top of the cylinder. If you can't feel it by touch you're good to go.
 

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Double check that all of the bolts are out then pry on it lightly. It doesn't use a gasket, it is siliconed on so it's not just going to pop off it will take some light prying
 

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A rubber mallet also helps.
 

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A ring kit is only $17.54 USd from the dealer for one piston if the ones you ordered aren't the right ones. GM# 21018813.

 

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Another thing to check is if the rings are pre-sized or not. Not sure on ecotec's if the rings come already to correct gap or if they are file to fit. Also make sure you get the orientation correct as well, don't have my manual in front of me so not sure what's recommended for these cars (general rule is 120* apart). Essentially you want to make sure the end gap is correct so the ring doesn't butt together when the motor warms up and lift a ring land and cause more damage and you don't want the ring gaps all lined up or real close to each other because it can give you compression/oil consumption issues. I'll try and look at my book tonight to see if it has anything.

Also if you ordered STD pistons, the oversized rings will not work. Order STD size rings.
 

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Discussion Starter #16
ok i found a new set of piston and rings that I ordered std for rings and piston,,, the pistons come in packs of 4 with rings and bearings,, should I just leave the other 2 pistons alone that are undamaged, or replace with the new ones while I have access to it?

and as someone listed above I should just use the same bearings, for ease,, should I just discard the bearings that came with these pistons as well??

thanks im just waiting on these parts to show up now
 
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