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Discussion Starter #1
May sound like a dumb question, but I've got my rebuilt engine sitting at #1 TDC but I don't quite know where to rotate/orientate the points style distributor.
I followed my rebuild by the book and installed the timing gears with the crank at the 12 o-clock and the cam at 6 o-clock. Since I'm at #1 TDC I should be setting the distributor to the #1 cylinder as usual correct?


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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If you set it up so that the crank gear dot is at 12 o-clock and the cam is at 6 o-clock, you're on the exhaust stroke. Put both dots straight up, and you'll be on compression.

Lars
 

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Discussion Starter #4
It's at TDC compression I believe, I watched the cam rotate and the intake valve closed.
According to the book (rocky rotella's rebuilding book) I can set up the time at 12 and 6 if I set it ignition timing to the #6 cylinder, but I'm wondering if I must set it to #6 even if I've rotated it around to #1 TDC.

It seems like, as long as I rotate the engine around to #1 TDC the marks will both be at the 12 anyway and I can ignition time at #1. I'm wondering how the distributor should be facing to be at #1

B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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Well, with the engine at TDC compression on #1 cylinder, the tip of the rotor in the distributor needs to be pointing to the terminal on the cap where you connect the wire to #1 spark plug.

Bear
 

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Discussion Starter #6
Where is that on the distributor? I don't have a cap with a #1 indicator, and the distributor isn't clamped in place yet.


Off topic Q? Anyone know the thread size on valley pan bolts by any chance? Mine disappeared.

B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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This is such a anti-technical method (requires no batteries) I hate to write it. But, I have always been able to figure it out or confirm it, with a piece of toilet paper :rofl: With the coil unplugged, and #1 spark plug removed, place a piece of toilet paper in the spark plug hole. When you rotate the engine and it is on compression stroke, it will blow the paper out of the hole. :lol:
 

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Discussion Starter #8
That's an outstanding method. I'm quite certain my engine is at #1 TDC compression. All I'm trying to do is orient the distributor that has no cap or markings for the #1 cyl.
And find the thread size for the valley pan bolts lol


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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Usually, my #1 position is pointing at the battery. If it is on the compression stroke and is at the TDC mark, the rotor should point that direction. You may have to remove the distributor, rotate the oil pump shaft to make that happen. When the distro is in place, rotor pointing at the battery, that is the place to install the spark plug wire going to #1 cylinder. 18436572 CCW Never seen that marked anywhere as #1.
 

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If you want to orient it the same way the factory did, then insert your distributor so that with your engine at TDC #1 compression the rotor is pointing between 12 o'clock and 1 o'clock (12 o'clock is directly at the firewall, 6 o'clock is directly at the front bumper). Make sure the distributor is fully seated down against the block. You may have to fiddle with it and/or take a long flat blade screwdriver and turn the oil pump drive shaft down inside the block so that it lines up with the tang on the distributor. The vacuum canister should point towards 3 o'clock (drivers side fender). Wire the distributor cap accordingly from there (counter-clockwise in firing order sequence 1 8 4 3 6 5 7 2). That's only if you want to orient everything the way the factory did it. In actual practice, with the motor again at TDC compression #1, just plop the distributor in (make sure it's fully seated all the way down onto the block). Whichever terminal the rotor happens to be pointing to is now #1. Connect #1 plug wire to that terminal, then again--- work your way around clockwise in firing order sequence 1 8 4 3 6 5 7 2.

Bear
 

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Discussion Starter #11
So it really doenst matter where the distributor lands, just as long as the firing order is set properly.


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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Correct. It only matters if you want to orient everything the same as it was from the factory. It's probably not a bad idea to go ahead and do that though, because Murphy's Law being what it is, what can happen to you with the "plop and wire" method is that you can find yourself in a position where you can't set the timing properly because the vacuum advance canister bangs into something and won't allow you to turn the distributor body where it needs to go. :D

Bear
 
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