Can these pistons be re-coated?
 

1987 3.2L, first time the engine had been open, 123K miles, one destroyed piston / cylinder (see my other thread for more info)
http://forums.pelicanparts.com/911-engine-rebuilding-forum/487948-guess-how-much-left.html

1) Is this cylinder skirt / piston damage likely caused by overheating?

2) Are the five cylinders worth re-plating (assuming they are within specs except for the scratches)? How would I get a sixth piston and cylinder?

3)Are the pistons immediately trash because of the scratching? ( I built and ran a motorcycle with similar scratches on the piston with no adverse effects)

Thanks,
Richard

http://forums.pelicanparts.com/uploa...1250177619.jpg
http://forums.pelicanparts.com/uploa...1250177647.jpg
http://forums.pelicanparts.com/uploa...1250177675.jpg
http://forums.pelicanparts.com/uploa...1250177694.jpg

I believe the KS marking on the cylinder indicates that your jugs are Alusil. They are not plated inside, but there is a very specific process to prepare them for new rings. You are already behind the game a little. You might concider sending your cylinders out to a company like LN engineering to have them Nickasil plated and replacing the pistons. The scratches on your pistons look worse than the cylinders themselves (hard to judge from photos though). Don't get too agressive working on them, because they should have a special coating to work with the alusil cylinders.
If those cylinders were on a customer's car, I would suggest replacement. If it was my car, and I was not planning on selling it soon, I might try to prep and re-ring what you have... knowing that $4000 is a lot of money to burn on the top end compared to my time tinkering.

I've assumed because of the year (1987) and that everything looked virgin to this point, that the cylinders would be the Nicasil type.

Now I need to know more... Any experts on cylinder identification?

Kolbien/Schmidt is alucil
Alucil has 10 fins on the 3.2
Bruce

Aw Crap!
I Got Alusil!

the bore is 95mm (Actually a little less by my inaccurate Calipers.)

10 fins, KS Marking, not a trace of magnetic
Now what?

honestly.... I just looked at your other thread, you really should sell / throw away (or make wall art out of) all your parts and buy a nice used engine with a clean bill of health & leak down. I predict the path you are on right now will be much more expensive than starting completely over.

Yeah that's likely the plan. But I've got two things working against me on that right now:
1) Poor poor poor. I don't have $5K to lay out all at once to buy a known good working engine.

2) If I buy another engine it's just a used engine that still needs rebuilt. Yes, Hopefully it starts out with good pistons, crank and cases. But it's a deal of not knowing what you get to start with because it has not been disassembled and checked out.

In all probability when I get done adding up how much it costs to fix what I have, the used engine plus rebuild will be cheaper. But I won't know unless I add it all up.

Richard

Rich, you have a PM

I'll bet someone on the board has a used set of in-spec Mahles.

Another, slightly more expensive option would be to send your cylinders to US Chrome or Milenium(?)for rebore and nikasil plating. You will need different pistons. Someone might have a set of used non-alusil pistons. I know they both sell JE, but don't know if you could use Mahles. It's worth checking for those of us with small budgets.

I have a set of good used in spec 3.2 nikasil pistons, if you want to go the replate the cylinder route. I dont need to make a killing off of them, I also have a new set of J&E, 9.3:1's for a 3.2 brand new in the box. I will make you a good deal if you need them.