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Discussion Starter #1
Background: I bought a 74 spider stock for $3k sight unseen and drove it from MI to CT. Oil looked good and lost less than a quart over the 800 miles. The coolant looked mostly clean and tested good at an oil change shop where I checked the rear end for fluid before the journey. Performance was OK and no smoke or odd smells. I only drove it another 30 miles when I was back in CT. (Dry compression numbers were high 180s to low 190s within 10%-never did a wet test.) Then, it ran cold so I bought a thermostat, but before installing it I decided to remove the unattached heater core and hoses and replace the windshield while the dash was out and the head gasket since there was oil leaking down both sides of the block, and well you know how it goes.

This is the first head I have pulled on a car. I've read Braden's Bible and many threads on the bb. Fortunately, I came across a member who said he stood in the bay, straddling the engine and lifted it off and that worked for me. Unfortunately, I wasn't prepared for the extent of carbon and oil and crap coating the valves and chambers and I was surprised to see the tell-tale mayo pooled up around the liners since the coolant and oil looked/look OK. Pics are attached.

Being new to this,
1. Is it worth cleaning and R&R this head and valve assemblies in this condition or is it more economical to buy a new head, etc. and send this one in as a core?
2. How do the pros clean a head that looks like this (some bath?) and the area where the liners are?
3. Will I need to pull the liners in order to clean out the emulsion and will I need to delve even further into the bottom of the engine if I pull them to make things right assuming the crank is OK?
4. Lastly, having never scene a blown head gasket before, does this look pretty typical or pretty bad?

Thanks for any experienced feedback. Paul
 

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Well, you should probably wait for the learned opinions of the professional mechanics...

I would guess the engine was burning some oil - that's why the combustion chambers are coated in oily/wet looking carbon. Plus the mixture may be a bit rich - that tends to leave a sooty black deposit. When a head gasket fails such that coolant gets into the combustion chambers the pistons/head can look very clean - 'steam cleaned'.

It is hard to say about the 'mayonaise'. There could have been a bit of oil leaking into the coolant or it could have been left behind after some previous work (never cleaned out thoroughly).

If you are NOT planning to remove the pistons/liners then DO NOT turn the crank/allow the pistons to move unless the liners are clamped down. Doing so without liner clamps can dislodge the liners ruining the seal between the liner & block. That can allow coolant to contaminate the oil - leading to disaster for the bearings.
 

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To my eyes that doesn't look all that unusual and will clean up easily with a wire wheel and elbow grease. I see no reason to buy a new head.

Hard to say about the deluted oil. You said it looks good - makes me think you're ok. How was the oil pressure? If the mains were worn from the deluted oil then the oil pressure would show low when hot.

Good luck!
 

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Agreed. The head looks fairly normal. Fill the combustion chambers with MEK (it is in the paint section at Lowes) and let it soak for a few days. It will loosen the deposits. MEK is very flammable so treat it like gasoline.

Do a good job of cleaning the threads on the head studs and nuts before you re-install the head. I once blew a new head gasket because there was crap in the nuts that gave false torque readings.
 

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If you are NOT planning to remove the pistons/liners then DO NOT turn the crank/allow the pistons to move unless the liners are clamped down. Doing so without liner clamps can dislodge the liners ruining the seal between the liner & block. That can allow coolant to contaminate the oil - leading to disaster for the bearings.
Yea, good point. Seeing a picture of a disassembled engine without clamps holding the liners in place is kind of like seeing a picture of a car without wheels supported by a jack - sorta scary.

You can make liner hold-downs from a large washer + a section of electrical conduit. You only need two - one to hold down #1 & 2, the second for #3 & 4.
 

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This sounds dumb but... What is the blue bag like thing in one of the pictures and why does my '74 not have one??
 

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You've gone to all this trouble so for heaven's sakes take the head to a machine shop. They will clean it up and regrind the valve and seat faces as well as check the wear on the guides. It depends on how many miles are on the engine but generally you are going to end up paying about the same to have your head rebuilt as you would to buy an already rebuilt one on exchange. The ready made will save you some time if you're in a hurry or maybe save you a bit if your head is trash for some reason (unlikely)

I don't know how many miles are on this engine but it looks to me like it's been running rich for quite some time. If it's a SPICA injected engine that's typical when the thermostatic actuator goes bad. Cleaning the carbon off of the piston crowns in situ would be tough and potentially problematic. definitely lock the liners down prior to moving anything if you intend to just slap the head back on and not get into the bottom end. The only real problem with the lower end might be the rear main seal, if it's leaking it's just gonna get worse.

As for the head gasket, the Alfa doesn't have a head gasket problem if the roll pin and o-ring mod has been installed. They were never actually prone to classic "blown head gasket" failures, it was just an issue of oil leaking into the coolant. It looks like you have the roll pins but make sure they haven't been pushed down flush with the block surface. If they have you might be able to pull them back up with something like an easy-out or you could just tap a new one in on top of the old one - it won't hurt anything. They have to protrude to at least the thickness of the o-ring (which are actually not standard o-rings but flat faced gaskets)

Personally I'm not one to do head jobs on engines like this with what appear to be quite a few miles. It's just a lot easier to pull the motor and go completely through it top to bottom and be done. These engines were designed to be rebuilt numerous times but to answer your question, if the mileage is not that high the bottom end should be fine.
 

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Discussion Starter #9
Thanks for the feedback, Gentlemen.

I didn't want to bother making liner hold-downs until I knew whether I was pulling the liners. Next move is to put some on, then clean out the emulsion with the liners in place. Then, I may pull the liners and piston heads, rehone/wash/wd40 and new hastings rings, proper break in, etc. I'm not sure that's necessary now with the dry compression numbers I had, but it might be a reasonable expense and insurance against pulling the head again within the next 10K miles.

The engine has 78K on it, but since the oil pressure always showed normal and I've never had to add coolant, I don't plan on pulling the engine now. I'll have to check the rear main seal for any leakage, though. Other key factors in not pulling it are my budget is tight and I also want to drive it and not maintain my bad habit of missing the warm months with an Alfa dissassembled. I'll bring the head to a shop that's been recommended and discuss what they could do and what I could do to keep cost down if there is any valve work, aside from cleaning and potential resurfacing.

As for running rich, it's a Spica and I had pulled the TA last fall and tested it via hot water bath. It extended at temp exactly as it should have (27mm) but, I question the validity when there is no resistance against the actuator like there would be when installed. Once the head's back on and all's timed, I'll go through the Spica and mixture settings again. (The Spica passed inspection when I first checked out the car.)

Jeff, the blue bag is for washer fluid, put in by the PO and not appropriate for a '74 in type or placement. If you don't have one, that's a good thing.

I'll buy some MEK if the shop doesn't clean this up, and I will definitely chase the head bolt/nut threads and clean/lube them prior to torquing.

Thanks again, Paul
 

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If you are planning on pulling the pistons out then you may as well plan on pulling the whole engine. I think it is possible to do it with it in the engine bay but I can only imagine how miserable that would be. You've got great compression numbers - I don't see the point.

And yes, you can certainly take the head to a shop but I would at least do a leak test: Install the plugs, level the head, fill the chambers with fuel and see if there are any leaks. If not I would just clean it up with a wire brush on the end of a drill motor (an MEK pre-soak is a good idea) and go with it.

You've got good compression, not burning oil, running a little rich (which would save your valves from burning), a little water in the oil, good oil pressure, and it is springtime. I say button it up and drive. Pull the motor in the off season and then you can clean up the engine bay and have at the motor at your lesure.

As far as the SPICA is concerned, the TA is always the prime suspect but far from the only one. The FCS could be miss-adjusted, The CSS could be stuck, etc. Once together, get John Stewart's tune up manual and carefully go through it step by step.

BTW, boiling the TA is the correct way to test it so if you are measuring 27mm then you are good.
 

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Not to hijack, but my '74 has the regular windshield washer bottle not a bag. Is that normal?
 

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The TA is hydraulic so load is not going to affect it's dimension. Sounds like you're okay there but, as mentioned, other things can be out of whack to make you run rich. Another possibility is that the deposits are from a previous condition that has since been rectified. How did the plugs look?

I'd agree that you have potential here for being able to just clean it up, put it back together with new head gasket and be good. Make sure the oil passage roll pins and seals are set up right.
 

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One note about the oil in the water....
If two of the O rings in the head gasket were leaking oil down the outside of the block, then some probably went into the water jacket also.
I would clean it up a bit ( don't worry so much about the carbon on the pistons and valves), put in the roll pins (don't see any now) and the proper O rings.
Button it all up with a good quality Reinz head gasket.
 

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Discussion Starter #15
Good deduction Kilgore Trout, with great pleasure I removed the A/C, knowing that it was dead weight and a mediocre performer even when working.

From what I can see, it looks like the gasket leaks were only on the exhaust side. The head with gasket pictures show trails of oil from each of the liner tops on that side extending to and along the outer edge of the gasket. Is there anything significant to that? Could the high heat of the exhaust manifold cause expansion of the head on that side that should have been retorqued at some point?

Oil was mixing with the coolant, and cloudy residue is evident on the high-water marks on the head bolts. What is a good way to flush the cooling system after I clean out the accessible muck and reinstall the hoses, rad, heater core, etc? The roll pins are installed in the block and all are protruding at gasket height. So that's good. I've got a Reinz as recommended. Thanks.
 

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Discussion Starter #16
checking head flatness

I'm under the impression that checking flatness is something that needs to be done by a shop. Is this true? Or, can I check it myself with a decent straight edge?
 

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You can check it with a good straight edge. Position the straight edge on the head such that you have a bright light behind it. The straight edge will block light all along its length if the head were perfectly flat. You can next use a feeler gauge to measure how far from perfect the head is. Do this along the length, width and diagonally.
 

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Pretty normal looking for 78K you done good. Whatever you do, don't pull the liners as said above. To really clean the head might as well take the valves out decarbonize and re lap the valves onto the seats and have the head resurfaced the minimum amount to get it flat if it needs it. My personal opinion is to have the head milled the minimum amount so you will have a good mating surface for the new head gasket but that's just me. Just have all mating surfaces super clean. I use the ultra grey permatex gasket maker on the back and around the front of the head gasket. Don't be afraid to ask questions. It is REALLY easy to get the while I'm in there itus diease so be strong:) Make sure you put all the fuel injection line supports back on. They are there for a reason. Mo photos and welcome to the board. I'm just finishing up a restoration of a 74 spider and it's been a fun journey, yours should be too!
What was your oil pressure at idle with a hot engine and at 3500 rpm?
 

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Discussion Starter #20
Thanks for the vote of confidence. Oil pressure was in the middle of the gauge when cruising on the highway and I estimate about 5 to 10 at idle.
 
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