Are these pistons useable?
 

I picked up a 3.4 from a shop who had removed it and taken it to bits. It looks like the crank and rods/piston assembly has been sat on the floor and has slightly marked the pistons...though I think some is engine use also.

On this one you can see the lighter areas where it looks like some coating has worn away? Also a few vertical scores though you cant feel them with a finger nail barely.
https://lh3.googleusercontent.com/-1...o/IMAG0361.jpg

This one similar lighter areas with some deeper marks from the shop floor...schmucks!
https://lh4.googleusercontent.com/-7...o/IMAG0359.jpg

This one similar


https://lh5.googleusercontent.com/-O...o/IMAG0358.jpg

Ignore the grit and mess on them....they need a clean!

Can they be lightly cleaned up with fine emery, or are they paper weights?

Thanks

IMO - If you're going through all the work in taking apart the engine, I'd make sure the pistons are pristine! I wouldn't touch them - but that's just me.

Why was the engine torn down?
What do the cylinders look like?
Do the ring grooves, ring end gap, O.D., and piston pin bore meet spec?

That piston doesn't look so good to me but looks can be deceiving.

What you are showing is not significant. Totally and properly cleaned that is nothing to be concerned with, IF they meet specs in terms of measurement. Careless handling for sure, but not an issue if they meet spec for size IMO. The big question is what would you be doing with them? The cylinders are critical and a simple inspection is not sufficient.

You WILL want to use new rings with those of course.

Sorry yes I ought to have said I am intending to re-line the 3.4 and mybe re use these pistons.

Those pistons have failed. One the iron coating has flaked off the next thing that happens is increased cylinder wear.

I have hundreds of good used pistons, we throw them away daily and never reuse them, even if they loo good.

Thanks for all the input