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Discussion Starter #1
I pulled the head after seeing engine coolant in the exhaust. Thread here: http://http://www.alfabb.com/bb/forums/gt-1963-1977/328577-out-season.html

Now that I can see down into the block, I may have another problem. The pistons have carbon only in the center. For you guys with more experience, does the clean outer edge of the piston tell you I am letting too much oil past the rings?
 

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But Mad North-Northwest
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I would think oil wouldn't remove carbon, it would cause it. Coolant removes carbon, though, which might explain why #1 looks cleaner around the edges. Perhaps that's the cylinder that was leaking.

Unless there were bad oil burning problems or compression problems before the head gasket job, personally I wouldn't worry so much about the rings and liners. Beware mission creep.
 

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The pistons have carbon only in the center. For you guys with more experience, does the clean outer edge of the piston tell you I am letting too much oil past the rings?
Gubi: I understand your reasoning, but I have had an old-time mechanic tell me that the clean outer edge on a piston does indicate that oil is getting past the rings.

Admittedly, it is hard to see the carbon pattern on pistons #2 & 3 in Ray's photo . #1 has the most classic "carbon in the center, clean at the edges" pattern.

Ray: Does the car burn or use oil? If it does, and given the pattern of carbon on your pistons, then it appears the rings are worn. Use Hastings 3-piece oil rings; not the cast iron ones that come with the Borgo P&L set. Something like these: https://www.centerlinealfa.com/engine-parts/1623 , but of course matched to whatever pistons you buy.
 

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But Mad North-Northwest
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I suppose it could be, Jay, but the only one that looks unusual there is #1. Could just be the picture, I suppose, but we know there was coolant in the exhaust...I'm more thinking that one cylinder was where the leak was which is why the carbon got removed.

Anyway, like you said the real test is whether it was burning excessive oil. If not, there's probably not an issue here.
 

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But Mad North-Northwest
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...and note that by excessive I mean "more than a quart every 750 miles or so". All three of my Alfas have burned ~1qt per 1000 as long as I've owned them.
 

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Discussion Starter #6 (Edited)
OK. I did the tear down almost immediately after the coolant smoke, so the clean edges are likely oil. All four pistons are the same way. I don't know the exact consumption rate, but it was definitely burning more oil than I am comfortable with.

That raises the next question: can I remove the short block, or do I need to reinstall the head temporarily in order to get the engine out?
 

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I suppose it could be, Jay, but the only one that looks unusual there is #1. Could just be the picture, I suppose, but we know there was coolant in the exhaust...I'm more thinking that one cylinder was where the leak was which is why the carbon got removed.
Yup, could be. While my conversation with that old-time mechanic was limited to oil leaks, I presume that coolant would remove carbon the same way. However, if there was a coolant leak at #1 on Ray's engine, would it be distributing coolant evenly all around the circumference? The symmetrical pattern of carbon on #1 seems more what I'd expect from oil getting past the rings than coolant coming from one bad spot on the head gasket.

But hey, who knows? As you wrote, it's easy to let "bracket creep" motivate you into replacing the P&L, bearings, oil pump, water pump, ..... while you're in there. On the other hand, once it's apart it's nice to get all the problems fixed.
 
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