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75 318 timing

THE-HOG

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I know to remove the plug and finger then turn the balancer. But with my finger in the whole and it pushing air out, how will I be sure I'm at top dead center? What's the tell? I may have answered my own question. When the harmonic balancer mark shows 0 on the timing tab, the engine is at top dead center with 0 advance. So then I install my distributor clocked so it is set to piston 1 after rotating on install, then it should just start? And I use the timing light?
 
Good beginning point. However... You can have the crank 180 degrees off. So without having the valve cover off and a pressure tester adapter, there's one way to find out. Give it a try, if it fires up and runs, excellent. If it won't fire up (don't try for too long or you might flood the plugs and it won't want to fire later anyway) and run spin the dist 180 and try again.
 
So then I install my distributor clocked so it is set to piston 1 after rotating on install, then it should just start? And I use the timing light?
Well that would depend on where the rotor is......................
The distributor can be installed just two ways due to the union of the slot and the tang at the interface. Assuming the number one is at TDC compression, then yes the rotor should be pointing to #1 Cylinder.(or #6 if in backwards). But that is only true if the guy before you installed the oil pump drive correctly clocked!
But honestly it doesn't matter where the rotor is pointing, so long as you install the #1 plugwire on top of it, and the rest in the correct firing order.

Another thing to do is to, before you slap the cap on, you gotta align the firing device.
If you have points, you gotta rotate the distributor CCW until the points just barely open ( not exactly critical).
But if you have factory electronic ignition, you just align the nearest vane to the pick-up pole-piece.
Now you can make note of where the rotor is pointing, install the cap and mark the tower above the rotor, and make that number one by installing the #1 plugwire on it.

Now, here is the secret, Mopar chose the position of the rotor-pointing-to number-one for exactly two reasons;
1) to standardize it on the assembly line and
2) cuz the factory plugwires are custom fit, and the lengths are pretty tight; so if you put it in "wrong", the wires may not all fit.

Theoretically, you could actually use any cylinder as a reference, at it's TDC compression, and aligning the rotor as above. You can even set your lawnmower in the same way, but instead of a rotor, you align the magnets to the iron-piece on the flywheel. Or your chainsaw, etcetera.
Good luck.
 
I have a point type distributor, can you please elaborate more on the points barely opening part? Also, does it matter which "nipple" of the circular collar is pointed at the doodad(sorry) I have one with a notch on either side.

4E8EF56A-23A7-422E-9A9C-BBDEB176DF3C.jpeg
 
The picture in post#4 is of an electronic Ignition distributor.
The gap spec on that one is set to in the range of .008 to .011, and is set using a Non-Magnetic feeler gauge. The gap is not super critical cuz I have seen then as tight as Zero, and all mine will work up to at least .030, the widest I have tried. The gap does not affect the Ignition timing.
For purposes of just getting the engine running, here's what I do;
1) I set the #1 piston to TDC/compression.
2) I install the D(distributor) with the rotor pointing in the general direction of the #1 cylinder. If the D does not drop down all the way, see Note-1
3) I then back the crank up to 10 degrees advanced. This will take care of all the approximations that follow.
4) then I push the Vcan CW until it hits the firewall
5) then I pull it towards me, CCW little by little until any vane lines up with approximate centerline of the magnetic pole-piece, in the center of the magnet. Snug the D down, plug it in, and install the rotor.
6) mark the OUTSIDE of the D with a vertical line pointing up to the rotor.
7) Install the cap. Whatever tower is above your mark is gonna be your #1. mark it, If no tower lines up, STOP! See note-2
8) install your #1 wire, the one that is gonna go to the #1 Cylinder into the marked tower. then Follow with the rest CW, in the firing order 18436572.
9) now you are ready to fire it up and set the Idle-timing.

Note-1
If the distributor does not drop down into the oil-pump drive, in that position, I just rotate the distributor a lil in either direction until it does. If it is off be very much, then I have to make a decision as to if I want to move it or not. Since it's my car, and my wires are all the same length, I can leave it exactly where-ever it drops in. But if your wires are custom fit/premade, they don't always fit properly, in which case I would pull it out and re-index the driveshaft, as many times as needed to get it in the ballpark of pointing to #1 cylinder. Once it's down, I install the hold down, loosely.
If you had to move the crank, then put #1 piston back to TDC compression.

Note-2
In the unlikely event that no tower lines up, within about 10/20 degrees, something is wrong. Recheck your work. Make sure the rotor advances on it's springs and snaps back to it's parked spot. If your work is good then the distributor cannot be used as it is, because the driveshaft is out of sync with the reluctor.
The Reluctor has two slots machined into it, one for CW rotation and the other for CCW. they are marked. Remove the rotor, and Find the slot. follow it up to the top of the reluctor, where the slot comes to the top face of the reluctor. There you should see the arrow pointing in the direction that your installed distributor rotates. If it is not pointing in the Correct direction, Just pull it off and reinstall it on the other slot, making sure it goes all the way down.
That reluctor is a light press-fit, and sometimes you have to pry it up, and sometimes you have to tap it back down. Then try again.
But
if a tower still does not line up, the D is made wrong and it will have to be modified, or thrown away.

Note-3
What you call a "nipple", I think you mean, the vane. There is one for every cylinder so for a V8 that would total 8. and
The thing you call a "circular collar" is the reluctor and the vanes are part of it; and
the stationary "Doodad" is the magnetic pick-up, usually just called the pick-up.
In the center of the pick-up is the pole piece.
As to the lines (notches) on the top of the reluctor, IDK what those are for.
The Pick-up is just a tiny electro-magnet. Every time a vane passes by the pole-piece, it sends a tiny voltage spike back to the ECU, which amps it up and translates it into something that the coil then uses to fire the sparkplug.

As always, Happy HotRodding.
 
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The picture in post#4 is of an electronic Ignition distributor.
The gap spec on that one is set to in the range of .008 to .011, and is set using a Non-Magnetic feeler gauge. The gap is not super critical cuz I have seen then as tight as Zero, and all mine will work up to at least .030, the widest I have tried. The gap does not affect the Ignition timing.
For purposes of just getting the engine running, here's what I do;
1) I set the #1 piston to TDC/compression.
2) I install the distributor with the rotor pointing in the general direction of the #1 cylinder. see Note-1
3) I then back the crank up to 10 degrees advanced.
4) then I push the Vcan CW until it hits the firewall
5) then I pull it towards me, CCW little by little until any vane lines up with approximate centerline of the magnetic pole-piece, in the center of the magnet. Snug the D down, plug it in, and install the rotor.
6) mark the OUTSIDE of the D with a vertical line pointing up to the rotor.
7) Install the cap. Whatever tower is above your mark is gonna be your #1. mark it, If no tower lines up, STOP! See note-2
8) install your #1 wire, the one that is gonna go to the #1 Cylinder into the marked tower. then Follow with the rest CW, in the firing order 18436572.
9) now you are ready to fire it up and set the Idle-timing.

Note-1
If the distributor does not drop down into the oil-pump drive, in that position, I just rotate the distributor a lil in either direction until it does. If it is off be very much, then I have to make a decision as to if I want to move it or not. Since it's my car, and my wires are all the same length, I can leave it exactly where-ever it drops in. But if your wires are custom fit/premade, they don't always fit properly, in which case I would pull it out and re-index the driveshaft, as many times as needed to get it in the ballpark of pointing to #1 cylinder. Once it's down, I install the hold down, loosely.
If you had to move the crank, then put #1 piston back to TDC compression.

Note-2
In the unlikely event that no tower lines up, within about 10/20 degrees, something is wrong. Recheck your work. Make sure the rotor advances on it's springs and snaps back to it's parked spot. If your work is good then the distributor cannot be used as it is, because the driveshaft is out of sync with the reluctor.
The Reluctor has two slots machined into it, one for CW rotation and the other for CCW. they are marked. Remove the rotor, and Find the slot. follow it up to the top of the reluctor, where the slot comes to the top face of the reluctor. There you should see the arrow pointing in the direction that your installed distributor rotates. If it is not pointing in the Correct direction, Just pull it off and reinstall it on the other slot, making sure it goes all the way down.
That reluctor is a light press-fit, and sometimes you have to pry it up, and sometimes you have to tap it back down. Then try again.
But
if a tower still does not line up, the D is made wrong and it will have to be modified, or thrown away.

Note-3
What you call a "nipple", I think you mean, the vane. There is one for every cylinder so for a V8 that would total 8. and
The thing you call a "circular collar" is the reluctor and the vanes are part of it; and
the stationary "Doodad" is the magnetic pick-up, usually just called the pick-up.
In the center of the pick-up is the pole piece.
As to the lines (notches) on the top of the reluctor, IDK what those are for.
The Pick-up is just a tiny electro-magnet. Every time a vane passes by the pole-piece, it sends a tiny voltage spike back to the ECU, which amps it up and translates it into something that the coil then uses to fire the sparkplug.

As always, Happy HotRodding.
Thank you, between the notches on the top of my reluctor indicated wishing way the rotor faces and spins. This is an amazing post. Thank you so much! But what is "the D"? The D shaped clamp that holds it then mark the body at the tower set for cyl 1?
 
D is my code for Distributor, cause it's 11 stinking letters long, and when talking about timing, that word gets typed a lot.
I used to type "Dizzy", but some guys over on FABO said it was gay or something. So I stopped. My apologies for not telling you in the post.
I edited the post to reflect my error.
 
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