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I am having my 72-2lit rebuilt but will not be able to get the car on the road to break in the engine/seat the rings until the coach work is completed and the glass in at least until summer. I would like to have the mechanic be sure the engine starts and is timed correctly which should happen within the next month or so however, I'm told that it is best to let the engine sit dry until I am ready to seat the rings. I hesitate to run the engine at all just to get it started without oil. Should we add oil just to get the motor started then drain it or start it dry but don't let it run long enough to heat up and risk glazing the cylinder walls? I'm open for suggestions. TIA!
 

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I would never purposely run an engine without oil. Who told you it's a good practice to run a rebuilt engine without any oil? After deglazing them, I've always wiped down the cylinder walls with engine oil, repeatedly, until the rag is perfectly clean and only a trace film of oil remains on the cylinder walls- no more what you'd leave on the metal parts of your gun or cast iron skillet to prevent corrosion during storage. Never had a problem with rings failing to seat properly. There's no need to run the engine outside the car anyway. If the engine turns freely by hand, and when you stop at TDC, the cams are aligned to the timing marks with #1 cylinder cam lobes pointing outward, and at that moment you note where the distributor's rotor cap is pointing and ensure the plug wires are routed correctly based upon that position, that Alfa engine will start and run just fine. However, if your mechanic insists upon it, then run it only briefly to make him happy, with oil in it, including filling the cam baths, then shut it down and don't run it again until it's time for the test drive with the car under varying loads. There's no need to drain the oil after a brief test run either, unless your mechanic tells you he needs to look for metal bits on the drain plug- then I would find another mechanic.
 

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Read the break-in instructions for the type of rings in the engine. It's normal to run the engine long enough to check oil pressure, timing, fuel is right, no leaks, without yet putting it under load. It won't hurt, but don't run it longer than needed for those checks. Then, when you can, break it in per the ring-maker's directions. Letting the engine sit in between won't matter. Don't run it without oil.

Andrew
 

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I'm just going to second what La Voce and Andrew said:

- A little idling / non-load use is OK. There is no other way to set the timing, check for leaks, etc.

- Sitting in the bodyshop for a few months with oil in the engine is no problem. It isn't as if fresh oil is corrosive. Draining the oil would accomplish nothing, as the inside of the engine will get thoroughly oiled in the first 2 seconds of running.

- Never run an engine with no oil! The bearings would fail immediately. Some people advise running a fresh engine for a couple of minutes with no coolant to cure the head gasket sealant. Re-torque after it cools down and then add the coolant. But you can't do this with oil.

Modern rings seat more readily than the old, cast iron rings. Seating rings used to be a black art; a few minutes of idling would supposedly "glaze" the liner walls forever. Today that isn't so much of a risk. Given the plan you have described, I think you'll be fine. But be sure to seal all of the engine's openings so that no abrasive dust from the body shop gets inside.
 

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I can't stress enough doing what your ring company recommends. Break-in instructions come with the rings, or go to the website and read up. I hear of engines (just heard of one this weekend) that have poor compression and/or oil consumption, with quality rings and knowledgeable trusted builders, and I've got to think it's how they're broken in, or not. Don't baby it, but don't overly thrash it.

In general don't use synthetic oil; use what the ring company recommends. There are break-in specific oils, which I have not specifically used, but probably should. I use a quality normal 30, 10-40, or 20-50, and my last several engines all worked in OK. Once you've changed the oil once or twice go to a synthetic if you're so inclined.

Andrew
 

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I've just done an engine rebuild on my 1800 alfetta , every thing put in is in stock form even the cam marks , I've got it started checked water an oil pressure , no oil leaks , the first drive on a flat road I didn't put the air filter on , in 3rd gear at 2000rpm I loaded it til til 4500rmp I let it come back down to 2000rmp ,I did this a couple of time , got back home an put the airfilter on left it to cool down , the next day I drove it for about 100km , thr car pulls like a steam train , I've used victor reinz head gasket an hasting rings :)
 

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Sounds right. I go out and do a bunch of similar runs on a freeway frontage road, can go slow and fast without bothering anyone. You want to let it coast down on a closed throttle too. Again, read the ring pack. Hasting are the main choice around here.

Also, by the time you break in it's too late to check/alter this, but a good honing matched to the rings is important too. My engine gurus say the stock honing that comes in Borgo and modern liners isn't that great, and encourage a flex-ball hone before assembly.

Andrew
 
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