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Discussion Starter #1
Just got the cam -shafts bolted back in, and looks like I'm out of time. I've been following Braden's procedure in the 'The Bible,' but looks like I've suffered a heretic's fate. The teeth on the shafts were never disengaged from the chain, but something has gone awry. May have happened when I replaced my fan. When doing the valve adjust I saw that my fan was going to go next time the car was started, so I ordered a new one and replaced it. Unfortunately I think in the process of taking off the old fan and tightening down the new one that the crank moved while the camshafts weren't bolted down. I can't imagine the chain jumped any teeth on anything, but who knows. Anyway, when I bolted down the cam-shafts and went to rotate the engine thru a couple revs, it won't move. Looking thru #1 spark plug hole, it looks as tho that's where some interference might be, so didn't want to screw anything up/bend anything. Question is now, how the hell to set it back to proper time? I made sure it was at TDC and all timing marks were spot on before starting this job.

Now, off to search the archives. Anyone near Southern NJ that likes to do this sort of thing....? :eek:
 

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At TDC the cam lobes should be pointing outward, and the marks should line up. If they don't I would imagine that removing the timing chain and putting the cams in correctly should fix it.Cylinder 1 needs to be at tic, with the cams posited correctly..
 

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Also make sure your distributor rotor is pointing to #1 otherwise you'll be 180 degrees off.
 

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Discussion Starter #4
When I started...

...as per Braden it didn't matter whether #1 was on compression or exhaust, just as long as it was on TDC. When I took it apart, both lobes were pointing AT one another, and marks lined up. I retracted the tensioner, then unbolted the intake cam. When doing that, the cam rotated clockwise due to spring pressure from one of the cylinder valve springs. No prob, still located on the chain.... Anyway, should I do the following:

1. Undo the chain
2. Unbolt the cams
3. Rotate engine to "P" mark on the crank pulley, and rotor pointing at #1 in Dist.
4. Bolt cams back in so timing marks are aligned (see below)
5. Fish chain so the link is at the top between the cams
6. Refasten chain
7. Release tensioner
8. Rotate a couple times, then back to cam-timing marks
9. Tighten tensioner bolt
10. Rotate a couple more times, and check timing marks (cams and crank)

From #4 above, One question I've been having, is given the pressure of the valve springs, how do you tighten the cams so they are positioned properly when the cam caps are snugged in?? Would really like to get this back on the road, and put my idiocy in the rearview mirror....:eek: Thanks
 

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It's hard to believe you got it so far off that you can't turn it. Try again, if you CAN turn it then turn it until the master link in the upper chain is between the two cams. To work with the upper chain first put a prybar down and against the tensioner sprocket, loosen the hoding bolt, pry it all the way in (fully loose) then retighten the holding bolt. Now you can turn the intake cam to provide slack in the chain between the cams. Undo the chain, position both cams with lobes out and lines matched, put the #1 piston at TDC, make sure the distributor rotor is pointing forward to #1 terminal on the cap. Reposition the chain so that the break is between the cams, hook it up - you need it tight on the driver's side and across to the intake cam after you reconnect it. Position it on the intake cam with it offset enough so that after you connect the master link you can turn the intake cam until the slack is gone and the index mark lines up.

WARNING - during all of this stuff or lay a rag across the opening so you won't drop the master link or anything else down into the sump. Take your time, be patient and forget all about schedules or deadlines. The whole point is to enjoy things like this - that's half of what Alfas are about.
 

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...the cam rotated clockwise due to spring pressure from one of the cylinder valve springs. No prob, still located on the chain....
The chain jumped a tooth (or two) on the idler sprocket. Do NOT try to turn the engine!!!
I've PMed you my number. Please call me tomorrow and I'll talk you through it.
 

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Obviously don't force anything but papjam is right, it wouldn't take much force to tweak a valve if you have an offset great enough to cause an interference problem.

I'll have to admit that I have never tried to do a valve clearance adjustment per the Braden method (without unhooking the chain) It was probably borne of the pain of having dropped the master link into the sump - which I have done (but only once) This is something I believe needs to be done the right way and trying to do it without unhooking the chain is a cheesy shortcut in my opinion (no disrespect to Pat who I respect and admire)

It's also not something that is done a great deal, you MAY have to do it one time between overhauls but usually you aren't going to have to touch them unless something wasn't done right to begin with or something has caused an undo change in wear or valve seat recession.

From this thread I can see that the basic problem of this method is a blind reliance, or let's call it "hope", that when reassembled all will be just as it was when you started.

Trust - but verify....
 
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