piston damage pics! your opinion?

[comsoldier20]

Just took off the head from my 1995 eclipse gst. mitsubishi claimed that the car wont start because the intake valves are stuck (bent) open. turns out they are right.

I am now trying to determine if I need to replace my piston heads. (notice the intake valve damage on them in the pics)

looking for some insight and opinions (hoping i can get away with using them)

these are pistons 1 and 4. (pistons 2 and 3 have similar damage)

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Thanks!

 

[DSMnoobsause]

If you see any cracks then I would say time for a rebuild. If not I would say your ok to slap a rebuilt head on.

 

[comsoldier20]

there doesnt appear to be any cracks, it seems that every single intake valve dug into the piston. exhaust valves look fine

 

[bastarddsm]

I wouldnt just carefully smooth the burs out.

 

[BogusSVO]

This is a common occurance.

Personally, I would drop the oil pan and pop the pistons out and make sure that the top ring still spins.
It is rare but has and will happen the valve will hit hared enough to pinch the ring.

If you do not want to do that, then rotate the crank so all 4 pistons are at mid stoke in the block. Then pour equal amounts on top of the piston and let set several hours, or over night.

When you come back if all the oil is till on top the pistons, you should be fine, but if you come back and the level on one or two has dropped way more than the others then you have a ring issue.

As far as the head goes, good chance you have cracked guides and those need replaced, when guides are changed, the seats need to be cut to set the seat index to the center line of the valve stem.

http://www.dsmtuners.com/forums/newbie-forum/341218-how-change-valve-guides-4g63t-head.html

http://www.dsmtuners.com/forums/cylinder-head-short-block/420045-how-have-4g63-head-rebuilt.html

Next to note are the valves you will have to replace, get OE 6T valves or a set of stainless steel. Other part store brands may be called OE Equvalaint, but be a 2 piece design, I would not use these for a turbo build.