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Discussion Starter · #1 ·
I am doing a head gasket on my 1979 Alfetta Sprint Veloce, and I noticed an odd thing, most likely the effect of previous maintenance. The #3 cam bearing cap (rearmost exhaust side) seems to me to be installed in the wrong orientation. Both the numeral "3" and the groove on the cap are on the opposite side compared to the other two caps of this camshaft. I have not been hearing any strange noises coming from the head, but then again this car is new to me, so I cannot claim to have much experience with the sounds of this engine. Any suggestions as to whether to leave this alone or put it back the right way?
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Are the rest of the numbers to the outside?
 

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I had this issue as well, 2 and 3 were backwards. What I did was to install them the way they came off, knowing that they were “worn in” that way. Then I checked camshaft turning resistance (no folllowers, chain off). Everything seemed ok and plastigauge gave me 3 thou so I said good to go
 
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Discussion Starter · #5 ·
@goats, thank you. However, I have a dilemma. The car has about 90k, and I do not know, when the last time was that the cams were off the head, i.e. whether it has had more miles with the cap in the wrong orientation or the other way around.
 

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Move the offending cap so number is to the outside. Running hot, note if oil pressure has dropped at all at any engine speed. (easiest to see at hot idle). If it drops, reinstall only that one backwards as it has worn enough to cause pressure drop when corrected. If pressure is fine, and since just one was wrong, correct the wrong one.
Last one that I had that showed a pressure drop, corrected, had 4 (!) of the 6 backwards and 2 in the wrong location! Messed it up pretty good.
 

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Plastigauge it with the head on the bench. It probably won’t matter but better to check ....
 

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Discussion Starter · #8 ·
Thank you. Will try what you suggest. I now wonder if this is the reason for having to change the head gasket. The reason I am changing it is that I have oil leaking out of the rear exhaust side o-ring, exactly next to the offending bearing cap!
 

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Try using Jon Normans block to head oil gallery connectors. NO more leaks!
 

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No camcap orientation has nothing to do with oil leaks from the o rings— gordon what does John have on this?
 

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Discussion Starter · #11 ·
I meant that it may be the locally elevated temparatures resulting from the improperly installed camshaft bearing causing wear to the o-ring. In any case, no matter what the reason, I have a leak through that o-ring, even though the head already has roll-pins (as referred to in Braden's book - is this what you mean by block-to-head oil galley connectors?)
 

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Early Alfa engines only had "O" rings in the head gasket. Eventually all leaked oil. The "O" rings would get funny and try to ooze into the head.
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This is a GTA head gasket with the "issue".
With the race GTA engines about '65/66 we experimented with different types and shape "O" ring, eventually settling on an early synthetic square cut ring as best. At Ausca, Ron Neal cut aluminum connecting tubes about 1/2 inch long, with a belt around the middle of the tube so it could not go down into the block gallery. With a square cut "O" ring around it leaks STOPPED. Jon Norman makes a kit with brass tubes and, I think, Viton "O" rings that I use now.

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For older 750 and 101 1300's and some 1600's a special installation tool is needed. Write me if you need to know about that. Tight fit in block, gasket on, "O" rings over the seated tubes, then head on.
These morphed into the 2L rolled head to block connectors that I don't like as they can get pushed into the block gallery, then an unaware builder installs another rolled connector on top and maybe oil flow to the cam journal is lost.
There are other types, some of plastic. I like the Jon Norman version because on pure race engines with worn cam bearings, you can make them into oil flow restrictors by tapping the ID part way down, installing an aluminum threaded plug, then drilling the plug with a small orifice to restrict oil flow. The aluminum ones we made at Ausca, were sometimes finished as restrictors.
Anyway, this works well, and is cheap insurance. I think the Norman kit is less than $20.
 

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Discussion Starter · #13 ·
Gordon, thank you. This is a wealth of useful information. I really do appreciate your help. I am tempted to replace the currently installed head-to-block connectors, if I can safely remove them. I already have viton o-rings that I got from Spruell Racing, but if I replace the connectors, I will go for the complete Norman kit. It looks just right.
 

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Old connectors are most easily removed with a hardened dry wall screw turned tightly into the connector. A block of plastic or wood on the block deck and then use a claw hammer as a puller or cutting pliers with a prying tool.
 

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Discussion Starter · #15 ·
After a hiatus because of a bicycling accident, I am back taking care of the head of my 1979 Alfetta Sprint Veloce. I measured the head for warpage, and I found a couple of spots where a 0.002 inch feeler would sneak under the straight edge, so I decided to take it to a machine shop for skimming (and do a valve adjustment, while the cams are being taken out). Braden's book talks about anything less that a 0.004 clearance being OK. Am I causing myself unnecessary trouble by skimming it for "only" a 0.002 inch issue?

I also have a question is about taking out the studs for the camshaft bearing caps. They seem a little too tight to me,and I do not want to break them. Anybody have experience taking those out? "Feel" of how they come out is hard to describe in a post, but any guidance will be appreciated.
 

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Why do you want to remove the cam bearing cap studs? To skim the head, only the lower exhaust manifold studs must be removed. The machinist will just support the head on a set of parallels that are taller than the studs.

If the exhaust studs are stubborn and will not come out with the "double-nut" method, I suggest you seek help from someone who has done this before. Repair of a broken stud usually requires a mill and angle fixture.
 

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Discussion Starter · #17 ·
@4sfed, thank you. The machine shop I talked to said they need both head surfaces free. Maybe I misunderstood. I wish I had your reply earlier. I already took the cam cap studs out. All came out easily.... except one. Ouch! I now have a broken cam cap stud that the machine shop will have to drill out. Can't figure out why the one was stuck.

BTW, exhaust studs were no problem at all. Same with lower row of intake. I messed up where least expected
 

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Machine shops have a variety of equipment, so it's possible they needed the cam cap studs removed ... fortunately for me, mine does not. The good news is that they're the easiest ones to fix. The exhaust and intake studs require setup on an angle plate.
 

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Discussion Starter · #19 ·
True that. No angle plate needed, should be an easy extraction; tempted to try myself, but not worth it since I am taking the head to the machine shop. On another note, I measured my valve clearances yesterday. All but one, on both sides came in one 1000th too tight (on both intake and exhaust sides - except one on the exhaust side which is way wide). Braden talks about valve stretching, which will get worse. In your experience, should I be worried about valve stretching, or just adjust them and let them be for a few more years?
 

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Discussion Starter · #20 ·
Another question about this head out of a 2000cc Alfetta GT. I am thinking of changing the block to head oil gallery connectors. The ones I found in the block seem terrible to me. They actually seem to be little pieces of sheet metal spiraled to form kind-of-a-tube. I tried the suggestion above of using a drywall screw to pull them out but they do not badge. Any other suggestions?
Gas Fish Composite material Metal Natural material
 
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