Yes, you have no choice but to take the chain apart where the master link is accessable.

Once you have the head off, you can re-arrange things so that the master link is accessable with the engine set to #1 TDC (e.g., both #1 cam lobes pointing outward, distributor rotor pointing ahead). Don't try to re-arrange things with the head and cams installed - the Alfa engine is an interference engine, and the pistons will hit the valves if the crankshaft is rotated without the timing chain in place.

Note that you can shift the upper timing chain's position on its lower sprocket pretty easily - just lower it enough to free it from the sprocket teeth, and you can shift it left <--> right.

 

Yes, you have no choice but to take the chain apart where the master link is accessable.

If you turn the motor over enough you will end up with the cams out and marks lined up. It's not a 1:1 ratio so sooner or later it will line up.

Correct gigem, If you rotate the engine enough the m/l will come to the topish with the cams pointing out. Chain works like a differential
where the same link will not land on the same tooth every time. The chain walks.

 

How the heck was this motor timed before with the master link in that position? I suppose it's possible but why?

Anyway, what Jay said...

 

Be sure you notice which way the lock goes! The rounded end goes the direction of the chain motion.

Also put a large rag down in the galley to prevent the links from going down into the pan. I can tell you pulling a pan is no fun if you don't have extra links laying around.

 

Because of what you are seeing the first thing I would do before taking anything apart is see where the distributor rotor is pointing. If it is pointing forward then that means the last time the cams were installed they were put in 180 degrees out and the way the PO rectified this would have been to swap the spark plug wires in the distributor cap. If that is the case you're going to want to get those back in the correct order when you put everything back together.

If the distributor rotor is pointing aft that just means that you are at #4 TDC rather than #1 TDC.

 

If you turn the motor over enough you will end up with the cams out and marks lined up. It's not a 1:1 ratio so sooner or later it will line up. Your distributor should be firing #4 now and will be firing 1 when you get them pointing out.
There are two schools of thought on the way the master link goes. some have the closed end on the right, the direction of rotation. I have it on the left and push it on with a small flat head screw driver. I'm not so worried about the link coming off from the motor accelerating faster than the mass of the link. I'm worried about the motor stopping faster than the link which if it seized up the link could not fly off. Everyone can do it however they want and I'm not looking for an argument. I've been doing it that way for 40 years and have never had the clip come off. I've broken the cam timing bolt from having my oil filter come off and not shutting down fast enough but that and a couple of bent valves was the only damage. That was the only oil filter that has ever loosened up on me in my life and with the wrench I got hopefully it will be the last.

 

If you turn the motor over enough you will end up with the cams out and marks lined up. It's not a 1:1 ratio

Right. I thought about this some more, and came to the same revelation. Obviously the chain is longer than the circumference of the drive sprocket, so the master link isn't going to end up in the same place with each revolution. Further, Alfa engines with different stroke lengths (1300 - 1600 - 1750 & 2L) use upper timing chains of different length, but the same sprocket diameters. So each of those will have a different multiple of engine rotation to chain rotation.

I'm not so worried about the link coming off from the motor accelerating faster than the mass of the link. I'm worried about the motor stopping faster than the link which if it seized up the link could not fly off.

Actually, I'm not worried about either scenario. The force due to acceleration/deacceleration on the snap link is trivial compared to the force required to pop it off. The thing weighs practically nothing - it would take about a million G's (*) to get it to unsnap. There is no way that the entire rotational mass of the engine could accelerate quickly enough to dislodge the snap link - the chain would fracture first.

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* OK, in thinking about this some more, perhaps "a million G's" was a little on the high side. How much force would you think it takes to snap the thing in place, say 5 pounds? And what would you guess it weights, maybe 1/4 ounce? So 5 # X 16 oz/# / .25 oz = 320 G's. Not quite a million, but enough to make Chuck Yaeger black out!

 

I guess that was my point, it really doesn't matter but going back to my Norton days it seems there was a certain way the master link clip faced. In other words I really don't know. What I do know is I've never(knock on wood) had one come off.

 

After sleeping on it I should have prefaced my remarks that it is entirely possible it was put together like that, probably was actually. Stranger things have happened.

 

Thanks all. I've been rotating the engine and it looks like it will line up after a few more rotations. It'll be a few more days before I get back out there again. Please keep checking for new threads as I'm sure there will be plenty more questions.