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Did they polish the crank bearing surfaces?
 

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I applied a little 'control' and 'variable' to this experiment:

I wiped off the bearings and crank, applied some oil, installed the crank and all caps...no turn. So that was 'control'.

I removed all the above, removed the #2 and #4 bearings, reinstalled the crank and caps...it turns.
Whoa! That sounds like the "smoking gun" to me. The #2 and 4 main bearings only receive oil pressure through the crankshaft oil passages. And, of course, all of the rod bearings are oiled the same way. It sounds like the STP created an embolism in a crankshaft oil passage that starved #2 and/or #4, leading to the bearing failure.

The condition of the rod bearings would also be suspect (I don't mean the bearing shells - I know you plan to replace those - I mean whether any of the rod bearings seized too - probably not, as that usually results in catastrophic rod failure).

Assuming your crankshaft and block aren't warped or damaged, the solution is to have the machine shop remove the oil galley plugs in the crankshaft, clean the passages with cylindrical wire brushes, and re-install new plugs.

A better fix is to replace the swaged-in plugs with tapped holes + allen head plugs.

The best fix is to cross-drill the #2 and #4 block and main bearings for direct oiling.

Sorry for the late reply - I've been travelling. Sounds like you already have your crankshaft back. You can try spraying carb cleaner (or some other aerosol solvent that comes with a wand) through the crankshaft oil galleries to ensure that they aren't still blocked.
 
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The best fix is to cross-drill the #2 and #4 block and main bearings for direct oiling.
That is unnecessary on an engine that will not see lots of action above 7000 rpm. I have been running a 170+ HP motor for years, regularly shifting at 7000 rpm and there have been no bearing lubrication issues (just sheared flywheel bolts!)

RJ has posted that the main benefit of cross drilling for direct oil to #2 & #4 mains is that it improves the oil feed to the rod bearings which are the ones that typically fail in race motors that have not been modified.
 

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That is unnecessary on an engine that will not see lots of action above 7000 rpm.
I will agree that the factory oiling system is adequate for normal use when everything is working properly. And I would never disagree with RJ.

However, you have to admit that an engine that directly oils the #2 & 4 mains has more redundancy than the stock system. In the event of an obstruction in one of the crankshaft oil galleries, having multiple sources of oil to the rod and #2 & 4 mains could be the difference between disaster and ho-hum. I am guessing that such an obstruction is what killed Shakey's engine.

So yes, cross-drilling #2 & 4 might be overkill. But overkill isn't always a bad thing.
 

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It is beyond "adequate for normal use". It is fine for high rpm/high power use. There is a probability that obstruction of the crank oil passages caused this problem and if so it is the first one that I have heard of. I lost a motor when an oil filter gasket blew out. It was an unusual event that did not demand re-engineering. If you really think that indirect oiling to #2 & #4 is such a risk that the block should be cross drilled then may I ask if you have done it to your motors?
 

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I must say that I raced A 1600 and 2L without the #2 and 4 drilling with no harm for years. I also changed oil every week, so no sludge ever accumulated.

Then one day the motor wouldn't accelerate. Found out it dropped a crank plug, and spun the #2 bearing into oblivion. Melted the block-side main, splunged the crank bearing. Welded up the damaged aluminum, line bored the block, replaced the crank, drilled and hex screwed all the crank galleries to replace the aluminum plugs.

Oh, and drilled the block....

You generally don't need the block drilled, until you should have done it yesterday. But if you are going to do it, be sure you go to a VERY experienced Alfa shop that has done this many times, has all the right jigs. Even if you have to send the block a long way. Do the job badly and the block is scrap. I think it's been mentioned that you need special proved bearings, and need to grove the block as well. Also RJ recommends a specific mod to the crank oil gallery(s?)

Robert
 

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sludge alone is bad...

Maybe sludge + STP was just too much to allow good oil flow? Mongo dunno.
My 'Alfa' mentor, Alex Bardi, always added a can of STP to his 1750 engine after an oil change. He never had any issues with his Alfa engines. I followed his lead for a few years but grew tired of adding the 'engine honey' as Alex called it. His father owned 'European Auto Imports' in the Marietta/Smyrna area of Georgia. They had some top notch mechanics, so maybe he learned it from them.

Frequent oil and filter changes do not hurt.

Mark
 

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Discussion Starter #229
I have no Alfa shop in the area, especially one that could drill oil passages in the block. I'll just have to go with the stock oil system. The good news is that our parts washer at work has nozzles that should allow me to flush the oil passages in the crank and block.

I'm pretty diligent about oil changes in all my vintage autos. It's a positive habit transfer from owning '55 Chevys and VW bugs that don't even have an oil filter! I don't usually run STP in each oil change, though. There wasn't sludge or metal in the pan, just some crud inside the crank.

There's no accounting for how this engine was treated by a PO.
 

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Discussion Starter #230
While I'm waiting for Classic Alfa to ship my order, I've been cleaning up the engine parts, removing old gaskets and adhesive, and cleaning carbon from liners, pistons, and valves.

I noticed this discoloration near the top of liner #2. It doesn't feel as smooth as the shiny surface of the rest of the liner. Is this anything to be concerned about?



The other three liners look fine.
 

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Any time one is different you should find out why. Have you looked at the pistons and rings? Sometimes the spring behind one of the rings has broken.

Robert
 

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Discussion Starter #232 (Edited)
Any time one is different you should find out why. Have you looked at the pistons and rings? Sometimes the spring behind one of the rings has broken.

Robert
Piston and rings look good; piston not the most carboned-up of the four. I'm replacing the rings, while I have everything apart.

I guess I'm concerned about the surface of the liner, and whether it will cause problems.
 

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Get the best Hastings rings. A bit more expensive, but very good and worth it.

To install new rings you will need to hone the cylinders. The V-shaped scratch pattern is key to getting the rings to seal. They wear and the cylinders wear together for a perfect fit. If you don't know about this, get your engine shop to hone the cylinders.

You also likely have a small ridge at the top of the cylinders - this is where the piston rings do not quite get to the top of the cylinder, so no wear. You will need to remove this or you can break a ring installing. Again have your shop take care of this.

Break-in is critical to getting rings to seal. There are threads on it - use the right oil, etc. RJ's thread will help you, as will JK's book.

While you have the heads off, you might consider getting the valve seats ground, and perhaps the guides replaced. And use the green Viton valve seals!!

You can notch the heads to allow greater cam clearance, allowing you to use RJ's super good custom cams. But you will need to install the valve guide in a special way to allow the higher lift of these cams. RJ can advise in great detail. Richard is quite an expert with a fully equipped shop. I shipped my head from SoCal to Florida to have him do all these things.

Thats Richard Jameson of RJ Racing. In the suppliers list.

Robert
 

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Piston and rings look good; piston not the most carboned-up of the four....
that blotchiness on the top of liner #2 ('piston not so carboned up') could just be a coolant leak into that cylinder.
(since liners are removed, do remember to check liner protrusion when putting them back with new O rings)
 

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Is number 2 cylinder why she seized, ie. She hydrauliced due to the cylinder filling with coolant?

This would explain why you are not really finding a smowing gun ... what does the head and head gasket look lIke around the top of number 2's liner?
Pete
 

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Discussion Starter #236
@60sRacer, I"ve got the Hastings rings. I have no problem with honing the liners to get the crosshatch right. there was no ridge on any of the liners...all four pistons slid smoothly out of the top.

The valve seats on the heads look good; I'll lap them when I replace the valves.

@spiderserie4, Do you think that liner discoloration is due to coolant?...it's up in the combustion area, next to the head. The head itself exhibits no such surface condition.

I'm wondering if I shouldn't just replace that liner. Is there any way to look at a piston or liner to tell if it's blue, pink, or green?

@PSk, The engine wasn't hydrolocked, but seized at the crank.
 

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Get the best Hastings rings. A bit more expensive, but very good and worth it.

To install new rings you will need to hone the cylinders. The V-shaped scratch pattern is key to getting the rings to seal. They wear and the cylinders wear together for a perfect fit. If you don't know about this, get your engine shop to hone the cylinders.

Robert
The hone grit needs to match what type of rings you get. For example chromed rings need the cylinder honed to a different grit then cast iron rings need. If the cylinders are not honed to the correct grit for the rings. They will either never seat in.
 

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Discussion Starter #238
Good point, @Jim G; I hadn't considered that. I looked it up, and Hastings recommends 220-280 grit for these rings.
 

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The hone grit needs to match what type of rings you get. For example chromed rings need the cylinder honed to a different grit then cast iron rings need. If the cylinders are not honed to the correct grit for the rings. They will either never seat in.
Do you choose the grit based upon the top compression ring? When I talked to the Hastings rep I was offered a choice of both top and second rings in cast iron or the top one chrome and the second iron. I am under the impression that the second ring is usually CI in the Hastings set.
 
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