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Discussion Starter #1
I'm slowly trying to resurrect a 1988 Spider that really should have been a parts car. I bought it not running and in many pieces (without an ECU or associated wiring harnesses, which I have since acquired through this great bb).

I pulled and then tore down the engine to happily discover it appears to have been rebuilt in the not-too-distant past. Pistons are in excellent shape with only a tiny bit of carbon which could be scraped off with a fingernail, the wristpins are tight and show no side-to-side movement and the liners have no discernible ridges at the top or bottom. The crank appears excellent and is now undergoing cleaning, as are the rest of the parts.

I ordered rings and bearings and sent the head to a shop in Tacoma that has been recommended a number of times on this bb.

I'm on a tight budget -- very tight. What I want to accomplish here is have a freshened engine that will run decently for 20K miles or so while I consider either building another, more race-like engine or pull this one and do it again with virtually everything new (including a more radical head, new liners and higher-compression pistons) with an eye on spirited street and track performance.

I'm wondering how much de-glazing should one do with the hone to prepare for new rings? I ran the hone through the liners (which are still in the block) last night and achieved the proper cross-hatch pattern per the Hastings literature. In general, the bores show bight, new metal. But, some dark areas (where the pistons sat dormant during it's two or three years sitting) still show through that nice, fresh pattern. I'm reluctant to keep at it with the hone trying to make all traces of that staining go away, not wanting to hog out the cylinders too much.

So, the question: when to stop?
 

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I'd stop now...

Was the engine burning oil and/or smoking from the exhaust pipe? If not, shouldn't worry about it, nor have taken the pistons/liners out.

According to the workshop manual, the max ovality and taper is only 0.01 mm or 0.0004. That ain't very much. Average diameter of a human hair (from your head) is only 0.003". You could put 0.0004" taper or make the bore out of round (ovality) with the hone. The best way to check is with a dial bore gauge, but if you still have the liners in the block the connecting rods will not allow you to check the bottom of the liner.

Put the engine back together using the same rings on the same pistons. Get it running and check your compression.

Save some money so you can do the job completely and correctly.

Should run another 20k miles even if the liners are out of tolerance. Might burn some oil. Buy a Workshop manual and study it.
 

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Discussion Starter #3
Thanks, Duke. I have a manual, but it doesn't give any detail on honing. I'll stop now and reassemble -- but with the new rings and bearings.

I have no idea if it burned oil in it's recent past, as it was all apart when I acquired it (an impulsive eBay purchase).

Attached is a photo of the state of the engine when acquired and after the pistons were removed (but before cleaning).
 

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If you have achieved a cross-hatch pattern and any glaze has been removed from the bores, you are probably ok. I went through this a few months ago, with Hastings rings, using a standard cylinder hone. I used a scrub brush along with soap and water to thoroughly clean the cylinder bores after honing and then applied a light oil very sparingly. Some suggest WD-40 or similar as the initial cylinder lubricant. I have had absolutely no problems with oil burning or consumption. Good luck and let us know how it works out.
 

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De-glazing

Wingwalker-

Impulse buying and taking apart a running engine to de-glaze the cylinders all point to the fact that you have the Alfa sickness! Welcome! I tell my wife its better than hanging out at the bars, casino, race track, etc. I once took the Alfa head to a local machine shop, only to get a call back a short time later that there was nothing wrong with the head, the machine shop was going to charge me next time for taking the head apart and putting it back together. Guides, springs and valves were all fine.

Good luck with your car, and welcome!

Duke
 

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Discussion Starter #6
Thanks, Duke.

Yup, not the first time I've taken on a project way bigger than it looked in the beginning. But you are correct; it does keep us away from the bars and the dancing girls, so my wife tolerates it.

The head off of this engine wasn't so fortunate. It had a few issues. But while it was at the shop, it received a slightly more aggressive intake cam and some work in the seat areas that should help it flow a bit better. Looks great now.

Larry
 
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