AMC/Jeep V-8 Engine Ignition Upgrades '72-'73


AMC used a Delco Breaker Points Ignition system in the V-8 Jeeps.
This is what I do to upgrade those ignitions from breaker points to magnetic trigger so I can install a more powerful electronic ignition.

This process isn't difficult or expensive, but it is time consuming, and if you are the type that gets into a hurry with things, this probably isn't for you.
Hand fitting of parts and attention to detail is an absloute MUST with this upgrade.

stock distributor
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Here is a shot of the stock distributor.
Find the #1 plug wire, and mark the distributor housing.
I scratch the housing lightly with a file, but your mark has to be perminant, otherwise solvents will remove the mark.

This is a good time to look for the timing mark on the harmonic balancer, and adjust crank pulley until it's pointing at the 0 (zero) Degree mark on your timing tab.
If your balancer timing mark is pointing at the 0 (zero) degree mark, and the distributor rotor is pointing at the #1 plug wire terminal mark, and the #1 cylinder piston is at Top Dead Center, you have now verified your distributor timing, balancer and crankshaft position.
If any of these aren't where they should be, click here for the low down on what's going on.


marked distributor housing
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Notice the mark on the distributor housing that the rotor is pointing at...
If the #1 Plug wire, Rotor Nose and Harmonic Balancer all agree, then all three are probably correct.
If not, you will have to verify Top Dead Center (TDC) of the #1 Cylinder before going any further.
Click Here For Instructions On Verification.


no rotor
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Here is a shot with the Rotor off.
Notice how the springs and weights are located for reference later.
See the 'Red Dust' on the Centrifugal Advance Head and Advance Weights? More on that below.


distributor
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Here is the distributor out of the engine.
Now is a good time to hold the housing, and try and move the distributor shaft sideways, top and bottom.
If you have very much play, it's time to replace the entire distributor with a remanufactured unit.
If the drive gear is severly worn, it's time for a new gear at the very least.
These are hard to locate in the aftermarket, so a remanfactured unit may be your only option.


Red Dust
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Here is a close up of the 'Red Dust' (oxidised iron) caused by high voltage getting through or around the rotor, and trying to weld the advance weights to the pivot pins.
This spark energy was supposed to be going to the spark plugs...

Lower Gear
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Here is a dissambled lower gear. There my be more than one thrust washer.

Oil Shellac Build up
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Here is a close up of the oil shellac that builds up on a distributor shaft.
The only way to get this shaft out of it's bushing is to soak the entire lower in a heavy duty parts cleaner.
I use a non acid based carburator cleaner made by 'Gunk'. It works very well, but will still may take several days to soften the shellac enough to remove the shaft.
DO NOT DRIVE THE SHAFT OUT! You will only succeed in driving out the top bushing!
Pull the shaft out as far as you can, use solvents & a wire brush. Clean off what you can get to, then push the shaft back in and soak it some more.
Eventually the varnish will disolve enough you can work the shaft out.
Once out, clean throughly with a wire brush before you reinstall.

wave ring
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Once the shaft is out of the housing, you have to remove the 'Wave' ring.
This is a delicate little clip, located at the top of the top bushing, and it holds the advance plate in the distributor.
DO NOT TAKE CHANCES WITH THIS CLIP! THIS WAVE RING CAN NOT BE REPLACED, Unless you rob another Delco Distributor for one.

... breaker points
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This is the Breaker Points attached to the Vacuum Advance plate.
The plate is Reused, the Braker Points get thrown in the trail box for someone that needs them.
You MUST mark the location of the breaker point contact arm, where it contacts the cam lobes on the shaft.
This will be the index spot for the upgrade parts.

vacuum advance plate
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Here is the vacuum advance plate, with an arrow marking the trigger point for the points.
It's very important to mark the point where the points arm contacts the shaft.
This is where you will want to locate the reluctor teeth from, and the pick up coil tooth later.
The second arrow is a ground wire, and it will most likely need to be removed.

trigger point location mark
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Here is another view of that vacuum advance plate with the trigger point location marked.

catch ring
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You want to pry this little grease sling catch ring off if your distributor has one.
It will just be in the way for the rest of the conversion.

Reluctor & Magnetic Trigger
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Here are the Reluctor and Magnetic Trigger I used.
I Think they are from a '76 Chrysler New Yorker with V-8 Engine.
(If you are modifying a 4 cylinder Delco distributor, just CAREFULLY grind off every other tooth on the reluctor.)

... centrifugal advance head 2
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This is the centrifugal advance head. Notice the cam lobes that activated the Breaker Points?
The lobes are VERY worn out, and this ins't a very old remanufactured distributor.
I am going to line up the cam noses with the trigger vanes on the reluctor.
You will need a round ('rat tail') file at the very least, but a Dremel style rotary tool is the fastest way.

Just take your time, getting this reluctor on neat and clean is everything!
Make sure the points on the reluctor align with the lobes on the cam, and try to keep the reluctor centered, by keeping the wall thickness uniform.

The grooves pointed out in the second picture must be greased before final reassembly.
Use a good quality synthetic grease, don't pinch pennies here, you only do this once.

bottom of centrifugal advance head
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Here is the bottom of the centrifugal advance head...
On the Left is unmodified, stright off the breaker points.
In the Middle is the Reluctor from a '76 Chrysler New Yorker with V-8 Engine.
On the Right is the advance head with the Chrysler reluctor fitted over the cam lobes for the breaker points.
Stright and even is the name of the game, so TAKE YOUR TIME!
Use some red thread locker, silver bearing solder, or JB Weld to hold the reluctor in place,
BUT ONLY AFTER YOUR FINAL FITTING.
If you stick it down now, It may be in the wrong place during final assembly.

Side Of Centrifugal Advance Head
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Here is the side of the centrifugal advance head.
The one on the left is right out of the Delco distributor, notice the cam lobes for the breaker points, and the Chrysler reluctor starting over the cam lobes.
The one on the right has the Chrysler reluctor fully in place.
The Chrysler reluctor in the middle (before modification) is from a '76 Chrysler New Yorker with a V-8 engine.

... Advance Head Installed
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Here is the centrifugal advance head reinstalled on the distrubutor shaft, and ready to go back in the distributor (except for one advance spring!).

NOW... Anything made for a CHEVY V-8 engine with a Delco Distributor will fit on your distributor for a cap and rotor!
This means you can now benifit from late model High Energy Caps, Rotors, Ignition Wires, Ect.
With a factory module from Ford or GM you can really make the old engine sing!

You can also use anything made on the aftermarket for Delco Ignitions, and MSD has a lot of great upgrades for Delco Distributors.
Any aftermarket Cap & Rotor combo made for a Chevy V-8 with points will fit on your vehicle now.
More when I get time...