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Discussion Starter #1
Hi Guys,

I would like to replace the timing chain on my 1978 Alfetta GTV 2.0.

Would anyone be able to tell me if this is possible without having to remove the cylinder head?

I have been told that the top chain is possible to replace without taking off the cylinder head however the bottom one does require the head being removed.
 

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Alfetta engine

You might find more help and advice in the spider and/or engine rebuilding forums as this is a 2.0L Nord engine.
 

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Richard Jemison
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Chain

The top one can be removed by separating the old one and connecting the new one to it with the master link, then dropping it down on the intake side and feeding it up on the exhaust side.
 

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I have been told that the top chain is possible to replace without taking off the cylinder head however the bottom one does require the head being removed.
You have been told the truth!

As alfar7 says, you can install a new upper chain without removing the head. I use a length of coat hanger wire, with a hook formed at one end, to fish the chain around the intermediate sprocket.

However, to replace the lower chain you'll need to remove more than the head. The front cover needs to come off, and to do that, both the head and oil pan need to come off. A lot of work if the engine is still installed in the car.

Why do you feel the chains need to be replaced? Usually this gets done as part of an engine rebuild.
 

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Discussion Starter #5
When the engine is revved I get random clicking/popping sound that seems to be coming from the front on the engine.

Also the engine seems to shake on idle. Both carbs and ignition timing have been checked and it was suggested buy mechanic to replace the chain and he believes that might be the cause
 

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Have you tried tensioning the chain? You just slack the retaining nut on the front of the engine on the intake side. Let it idle for a few minutes and with the engine still on tighten the nut. This should cure your problem.
 

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But Mad North-Northwest
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Definitely adjust the chain tensioner, but please don't do it with the engine running. That is the old procedure and is somewhat dangerous.

Do a search: there is a safer way to do it by removing the valve cover and moving the tensioner with a pry bar.

If your mechanic doesn't know about this adjustment you may want to find a mechanic who has more of a clue on Alfas.
 

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Spannermans simple timing chain adjustment.
DO NOT START THE ENGINE.
Select 4th gear
crack tensioner nut
Gently roll car forward letting engine turn only a few degrees.
Lock up tensioner nut
Don't let the engine turn backwards doing this.

Done
 

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But Mad North-Northwest
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10,535 Posts
Spannermans simple timing chain adjustment.
DO NOT START THE ENGINE.
Select 4th gear
crack tensioner nut
Gently roll car forward letting engine turn only a few degrees.
Lock up tensioner nut
Don't let the engine turn backwards doing this.
That's the basically the procedure in the service manual for my '91 Spider, however the manual specifically says to move the vehicle backwards and forwards. So it doesn't seem like backwards is actually a problem.

However, the issue with this procedure is that the spring on the tensioning sprocket isn't very strong, and in some cases will not actually take up enough slack. The procedure recommended by Pat Braden is basically to slightly loosen the tensioner lock bolt, manually pry the tensioner tight with a long screwdriver, and then tighten the bolt.

Do a search and you'll find more details. Do not over-loosen the lock bolt or the tensioner pieces will fall into your sump.
 

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Turning the engine backwards with the tensioner nut released WILL cause the tensioner to compress and the chain to slacken off potentially letting the chain jump on the gears.
All timing chain and belt tensioners are on the slack side of the chain/belt when the engine is turning for this reason.
 

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Also the engine seems to shake on idle. Both carbs and ignition timing have been checked and it was suggested buy mechanic to replace the chain and he believes that might be the cause
I haven't seen/heard/felt your engine shake on idle, but I'm skeptical that a loose chain would produce that symptom.

Agree with the above posts recommending that you tighten the upper chain before replacing it. Also second Gubi's advice to not do it with the engine running.
 

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Loose chain

I have never heard of all these new procedures. Ya learn something new every day. I was just going by the Haynes Alfetta manual of yesteryear. They got the information from Alfa. I have been doing it like that for years without ever a problem. But I guess I will bow to the new way. Anyway, tighten your timing chain and adjust camshaft sprockets if necessary.
 

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I have never heard of all these new procedures. Ya learn something new every day. I was just going by the Haynes Alfetta manual of yesteryear.
Not sure it's old versus new. More risky versus safe. Loosening the nut, running the engine, tightening the nut would probably work 49 times out of 50. But if the engine backfired during starting, you might get the cam timing far enough off to result in valve-piston contact.

The lower speeds & forces involved in Gubi's procedure just make it a lot safer. Sure, it will take another 10 minutes to remove & replace the cam cover, but while you're in there you can assess the condition of the chain, and use a screwdriver to add some force to the spring behind the tensioner.

My own procedure: with the cam cover off, use a cam turning tool to turn the exhaust cam fully CW (as viewed from the rear) taking up any slack on the exhaust side. Then use the tool to turn the intake cam CW, taking up any slack between the cams. Then loosen that nut, pry out the tensioner, retighten the nut. Replace the cam cover.
 
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