HEI Problems

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hoosierdaddy

hoosierdaddy

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I'm doing the HEI conversion on my 72 Duster (D1906 Mod , FD478 Coil) and I think I have a problem with my coil . When I turn the key on I have constant power at + and - terminals , no pulse on the - terminal . Am I dealing with a faulty coil ? I'm hoping someone here can help the response time on the /6 board is a little slow sometimes.
 
Nope, the module is not triggering, the coil. Is the module grounded? What distributer are you using? Is the dist triggering the module?
 
Charrlie_S said:
Nope, the module is not triggering, the coil. Is the module grounded? What distributer are you using? Is the dist triggering the module?
Click to expand...
I'm using a Mopar electronic distributor from Northwest AP and yes the module is grounded . I'll check distributor next but I don't think I'm getting any signal from the distributor .
 
Have you checked FOR CERTAIN that you have power DURING CRANKING?

You must connect IGN1 and IGN2 together as the "run" voltage goes dead during cranking. IGN2 is traditionally the brown wire going to the old resistor connection on the coil + side

Also, HEI DOES NOT draw coil current when stopped with key "in run". This means that the coil NEG will "read high" unlike the Mopar ECU which draws current if the key is left "on"
 
67Dart273 said:
Have you checked FOR CERTAIN that you have power DURING CRANKING?

You must connect IGN1 and IGN2 together as the "run" voltage goes dead during cranking. IGN2 is traditionally the brown wire going to the old resistor connection on the coil + side

"
Click to expand...

Correct, forgot to mention that. Also along the same thoughts, the ballast resistor should be removed from the circuit.
 
If you want, send me a message, and I'll give you my cell number. I will try and talk you through trouble shooting. Make sure you have a volt meter handy, when you call.
 
hoosierdaddy said:
With the key on shouldn't I get 12v on coil side of the ICM ?
Click to expand...

Yes. If you connected ALL wires off the resistor together you should be good but I would check........just hook your meter to coil+ and crank the engine using the key. You should get at least 10.5 V or more while cranking

There are TWO ignition voltages, only one of which is "hot" at a time.

The IGN1 (ignition run) coming from the key IS ONLY HOT in the "run" position, it s DEAD in cranking

So the IGN2 (coil resistor bypass circuit) which is traditionally brown, is hot during cranking. THIS WIRE IS separate from the yellow "start" wire

This trips up a lot of guys
 
I don't have 12v on the coil side of the ICM and I don't have anyone to crank the engine while I check voltages .
 
hoosierdaddy said:
I don't have 12v on the coil side of the ICM and I don't have anyone to crank the engine while I check voltages .
Click to expand...

Alligator clips on the test leads with the meter sitting on the cowl so you can see it through the windshield.
 
Update I had the ICM checked today and according to AZ it's working . I discovered that I'm only getting 1.31v on the coil side of the ICM . Where do I go next ?
 
hoosierdaddy said:
Update I had the ICM checked today and according to AZ it's working . I discovered that I'm only getting 1.31v on the coil side of the ICM . Where do I go next ?
Click to expand...

What do you mean "the coil side?" Here is a basic diagram, 4 pin?

Also NOTICE the specific hookup on the pickup........It must be so, or the relationship between the trigger and rotor will be "off" causing "rotor phasing" problems. You can Google that

With key in "run" or in "start" there should be battery voltage at coil+ and at the indicated terminal on the HEI (top left)

4pin-jpg.jpg
 
67Dart273 said:
What do you mean "the coil side?" Here is a basic diagram, 4 pin?

Also NOTICE the specific hookup on the pickup........It must be so, or the relationship between the trigger and rotor will be "off" causing "rotor phasing" problems. You can Google that

With key in "run" or in "start" there should be battery voltage at coil+ and at the indicated terminal on the HEI (top left)

View attachment 1715175876
Click to expand...
Sorry I meant to say 1.31v on the distributor side of the modulator . I'm actually getting 12.4v on the coil side of the modulator
 
Rather than burn up the starter motor spinning your engine, at this point you might remove the distributor and spin it by hand. Connect a spark tester directly to the coil HV lead. Once you get a spark that way, work your way back to final setup, checking spark at each step. I don't know if the wiring polarity shown for the pickup in post 17 will always be correct (i.e. male plug from distributor to wide terminal of HEI). Generally, people have to try both polarities when adding an HEI module.
 
As it turns out I decided to reinstall my points ignition until I can go over this and fully understand the process . I am going to check the components to make sure I don't have a hardware failure
 
I would not do that...........As suggested, pull the dist and module out of the car and "rig" it on the bench to test. VERY simple and VERY easy

Temporarily mount the module on a scrap of aluminum or steel. You don't need thermal grease, and the heat sink does not need to be very large.

"Rig" the two distributor connections as shown in the diagram.

Lay the coil out with a spark tester or spark plug "rigged" to the tower. Ground the tester or plug to the BATTERY NEG connection, not the coil can. The coil can is not ground

Hook NEG coil connection to the module as shown.

Hook POS coil connection to coil as shown

Hook the battery pos up as shown and spin the dist.

IF IT does not work, and you say you had the module tested.........

1....Post a clear photo of your hookup here

2...Hook your meter to the two distributor terminals. Spin the dist. shaft. It should generate about 1V AC. Not DC, AC

3...Inspect the interior of the distributor. Look for strike damage on the reluctor/ pickup, and for rust and debris stuck on the two. Check the shaft for wobble.

Get yourself a BRASS .008 feeler gauge. About a year ago, Oh'Really?s auto parts actually had these......along with spark testers
 
stash that points distributor in your trunk, you'll need it one day.
 
Thanks for all the response but I have already installed my points system , at the moment I'm so busy at work I don't have time to work through this and I needed to make the car drivable . As time allows I'll set up a bench test and work through it that way .
 
That's the smart way to do it...when you dont need it to work! Points always seem to work, like Carter carbs....:)
 
One advantage of the conversion kits for points distributors is that you can keep the points in the trunk to swap over on the road. For years I used a Crane Cams XR700 in my 69 Dart and 65 Newport. The Newport died once during a drive. I had an inline spark tester in the trunk to verify no spark. Fortunately, I had a spare XR700 ignition box in the trunk too, so swapped that. Fired right up and drove home. Swapping the whole slant distributor is fast, but can be a gunky job. I have had to remove one on the road when the plastic drive gear was giving problems. Keep hand cleaner and paper towels in the trunk too.
 
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