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Discussion Starter #1 (Edited)
My first time doing any actual engine work. Going to change all the top-end gaskets, have the carbs rebuilt and maybe have the head rebuilt.

I hope you can help me with these mysteries. I hope these attached pictures work...

1. One picture shows the valve cover breather fitting. The big hole had a hose on it that went to the air filter. The small hole had a small hose going to a small fitting on one of the carbs. What is the purpose of that small breather hose to the carb? Is it important?

2. Another pic shows a blanked-off nipple on that same carb. Near dead center of the carb pic. What is its purpose?

3. No pic for this one. After removing the valve cover, I can see that the cam timing is way off. When one cam has its timing mark lined up the other is a good 5mm off. I understand the instructions on how to fix this, but how does this happen? Has the chain stretched? Should I replace it?

4. Lastly, a pic of my valve cover, with two weird plastic patches on it, riveted to the aluminum. Only the rivets penetrate the aluminum. There are no holes under the plastic patch besides those. *** are these patches? A previous owner converted from SPICA to Dell’ortos. Does that explain? These rivets leak oil. I had planned on drilling them out and having someone weld the holes closed. Thoughts?

Thanks!!!
 

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I'm sure others will chime in but here is some basic stuff. Your car didn't come with carbs originally, from the factory it had Spica fuel injection, so everything about your intake is kinda, made to work... The plastic plates on the top of the valve cover used to have 1.5" tall vertical bits front and back to locate a hot air tubing that came over from the exhaust to the original air filter box. Sorry, I don't know much about dellorto's.

Cheers,
 

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The flange on the peg board, that bolts to the valve cover: Large port goes to the bottom port of the inner fender mounted oil separator, and the small port is for the hose from the fuel tank vapor reservoir.
I don't know about the capped port on the carburetor. Probably not used on this Alfa carb conversion.
When you checked the cam timing, did you first, properly adjust the timing chain tension and bring #1 cylinder to TDC using a dial indicator (or similar)? Don't trust the arrow (and mark on crank pulley) on the water pump. After finding true TDC, you can adjust the arrow on the wp. It is possible that the previous mechanic was playing with cam timing, or just assembled it incorrectly. Are the cams stock? Some aftermarket and performance cams require a non-stock cam timing.
Go ahead and weld the holes on the valve cover. Wrinkle paint or polish, if you like.
 

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Discussion Starter #4
Thanks Andy.

The small port on the breather fitting is connected to a tube that ran inside the valve cover over to the exhaust camshaft side, and the hose was going to a carb. This is for fuel vapor?

I observed the cam timing marks were off after removing the valve cover and before doing anything else.
 

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I have Dellortos on my 76 Spider. That plugged port is probably a vacuum line. Mine don't have it. I would ignore it. Just make sure it's not leaking. As far as the valve cover goes what other people have said is what is happening. You can find one without those clips as I have one in my spare parts stash. I think I took it off a 70 71 Berlina but am not 100% sure. Regardless I am glad I saved it as I am going to polish it and use it on my Spider.
 

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Discussion Starter #7
You guys are the best. Thank you.

So far everything is going exactly as Pat Braden said it would. Some tasks I was worried about, like the exhaust manifold bolts and the block coolant drain plug, turned out to be not quite impossible after multiple hours of trying, just as he said. They are done. Tonight the head comes off (God willing).

:)
 

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Be sure and take photos of how things come apart. They'll be an enormous help in keeping you away from the Great Unknown . . .
 

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Discussion Starter #9
Be sure and take photos of how things come apart. They'll be an enormous help in keeping you away from the Great Unknown . . .
So far it seems that any photo I could possibly need already exists on this website. I would not have attempted this otherwise. I bought every book on the subject and read every thread on the subject, so I actually feel very well prepared to do this.

It’s amazing the little tips you come across. Like duct taping the block coolant plug and washer to the wrench socket in order to get it started back in its threads, or refraining from cleaning the tops of the pistons no matter how bad they look. These tips are gold, and I would not have figured them out on my own.
 
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