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Discussion Starter · #1 ·
I'm disassembling my 396 to install a new cam kit, intake, etc and have reached the point where I am ready to remove the old timing chain. I want to position the motor at TDC on the #1 cylinder prior to removal. The problem is that when I determine compression stroke by placing my finger over the spark plug hole, then turn the crank up to point where the timing dots line up on the timing gears, the mark on the crank sprocket winds up at 12 O'clock, but the cam sprocket is also in the 12 O'clock position. I'm sure I have approximated TDC by looking at the valve positioning and feel that maybe the cam sprocket has been installed improperly. Has anyone ever run across anything like this? I'm a little uneasy going any further until I figure this out. Any ideas?

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TDC marking on the balancer is not quite what you think. To find mark TDC on your balancer:
1. Get a TDC locator (about $10-$12), a brass "bolt" with a hole all the way through it to make turning the engine easier.
2. Thread the bolt into the #1 spark plug hole. The further you put it in, the less cranking you will need to do.
3. Turn over the engine (I would do it by hand, it's easier if all plugs are loosened or removed) until the #1 piston stops against the brass bolt.
4. Make a mark on your balancer at the 0° pointer.
5. Turn over the engine in the opposite direction until the #1 piston hits the brass bolt again.
6. Make another mark on your balancer at the 0° pointer.
7. Using a cloth ruler (sewing supplies), measure the exact center between the two marks you just made, and mark your balancer, which will be your final TDC mark.
 

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No problem there, TDC on the compression stroke for #1 cylinder has both "dots" straight up. When the cam gear mark is facing down at 6 O'clock and the crank gear is straight up at 12 O' clock, the #6 cylinder is at TDC. You can't have the cam sprocket installed 180* out of phase on the cam face. It is physically impossible. It is just easier to align them during the install when they are facing each other. #1 will still be at TDC, but not on the compression stroke. Put it together with the dots facing each other, adjust the valves and then install the distributor correctly for #1 TDC on compression stroke. I assume you are simply installing a new cam and not degreeing it in?
I hope that was clear, if not....post again.
Jim

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Discussion Starter · #4 ·
Thanks to both of you for the help. I've got a handle on it now. This is my first time doing this and my head just wasn't on straight.
 
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