HEI issues!

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moffetkustoms

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Hey everyone! Have a 73 225 that I converted to the HEI swap. Have gone through the threads as directed by SSDan and others and still fighting a no start issue!!! Hooked both the ignition run wire and the ignition start wire from the ballast resistor together and have them triggering the relay for coil. Hot wire directly from battery to relay. Ground wire directly to battery from module/coil/relay bracket as well as the bracket grounds. Have installed a new distributor and replaced the ecu module a couple of times. Have even tried to find someone to tell me how to Ohms check the module with no success. I'm really missing my seat time in the Scamp. Any Suggestion??????????
 
When you say you ran a wire from the battery negative to the “module/coil/relay bracket” , do you mean you grounded the bracket that holds the module, coil, and relay, or do you mean that you grounded the module, and you grounded the coil, and you grounded the relay, and the bracket? I’m sure you mean each individual item, but just making sure.
I take it this is a new install, not an HEI that was previously running and now has a no start issue, correct?
The distributor drive shaft wasn’t installed 180° out what is it?
Can you post the wiring diagram you followed?
 
Did you work on any other wiring? Starter relay, NSS, or anything else?
I’m not very familiar with some of the features of the newer models. 73Ha ha, -“newer models”
It may or may not help you in this instance, but have you downloaded a wiring diagram from mymopar.com?
Hopefully some others will chime in here, because really that’s about all I’ve got.
 
If you are getting nothing (no spark), you should go back to the basics and check to verify that you are at least wired like the attached drawing (relay not withstanding).
Make certain you have a ground wire going to the module at the attaching screws (don't rely on just metal to metal contact from the screw/mount), and that you have +12 volts (battery) at the B terminal of the module and the + side of the coil. You must use 'Heat Sink Paste' (NOT dielectric grease) between the module back and whatever you are using for a heat sink. The module will cook itself in no time without a proper heat sink.
There is no test for the module using a multi-meter (you need a Module Testing machine), so all you can do is verify that it has all the inputs.
Back in the day, we just checked for all inputs and then replaced the module if all looked good input-wise. If everything looks good with the ignition circuit, then I would just go back and make certain the distributor was at least in the ballpark. That is to say, rotor is pointing to #1 plug terminal on the cap while #1 cylinder was at top dead center compression stroke.
If all is well with the HEI setup, you should at least get some sort of spark at the plugs.
HEI-Basic.JPG


Good luck.
 
I would "dewire" it enough to simplify the wiring, "hot wire" it to eliminate vehicle harness problems and therefore determine "Is the problem" in the new ignition, or in the vehicle wiring?

One of the guys (Trailbeast I think) drew up this nice neat diagram.

4pin-jpg-jpg.jpg


The module "tit" must be cut/ filed off the bottom.
The module MUST be mounted flat on a heat sink. Heat transfer "grease" is recommended but I have not used it.
The module MUST be grounded via the mounting holes.
Wire as shown here and temporarily connect the lead to the coil+ to battery to test

NOTICE THE COLORS and orientation on the pickup. Reversing them will not cause the thing to "not spark" but it will MOVE the timing of the spark in relation to rotor position, which is known as "rotor phasing" and will cause crossfire, missing, and rough running.

If you have a tach connected I would temporarily remove it. You may have moved the tach wire and snagged and bared the wire and caused a short, etc.

In other words simplify the system so you can figure it out.
 
You could always go back to stock. It's been working fine for decades!

"The parts you don't add, don't cause you no trouble" C. C. Nance
 
Have you had any welding done recently? I ask because I cooked the hei module on my run stand welding on it. Now it gets unplugged if I need to weld.
 
upload_2022-7-1_9-6-19.png

MSD has a nice diagram also that has the pins on the module labeled.
 
Dana67Dart said:
You could always go back to stock. It's been working fine for decades!

"The parts you don't add, don't cause you no trouble" C. C. Nance
Click to expand...
The problem with "stock" is that so far as I know there are no truly good quality replacement modules, anymore. Hell, HEI ones are suspect!!!
 
That's why I bought up a pile (~3-4) of new modules I found on eBay with old looking packaging, and from brands not commonly seen any more such as Niehoff, Filko, and I believe I have 1, KEM.
Brand new parts made before "made in CHINA" was ever a "thing".
 
67Dart273 said:
The problem with "stock" is that so far as I know there are no truly good quality replacement modules, anymore. Hell, HEI ones are suspect
Click to expand...
Points have worked fine for decades as well!
 
67Dart273 said:
The problem with "stock" is that so far as I know there are no truly good quality replacement modules, anymore. Hell, HEI ones are suspect!!!
Click to expand...
The Hi Rev 7500 I got from Jegs is good so far. I have no complaints.
 
Dana67Dart said:
Points have worked fine for decades as well!
Click to expand...
Well we are in the same boat with "points." You cannot buy high quality points anymore, like the old Echlin Gold, Accel, or Blue Streak. And just about ANY "parts store" condenser/ capacitor you buy, you BETTER leak test it. --And I don't mean with an ohmeter

The outboards I screw with---I don't even use OEM style caps. I use "orange drop" plastic caps. I desolder (they seem to be med. temp silver brazed) the bracket off the original cap, and heat shrink the orange drop to the bracket, after soldering one lead to the bracket for the ground. "So far so good." I have yet to have an orange drop show ANY leakage. NONE

I've been using .22mfd at 200v in the outboard magnetos

orangedrop.jpg
 
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Moffet,
The FIRST thing to check is that in crank & run you are getting 12v to the 'B' terminal on the module. Might be slightly less due to voltage drop/how you wired up, but close to 12v. If 12v is missing, then you need to check the wiring. If 12v is present, it narrows down the suspects. There is a drawing on the web where you disconnect the p/up plug & ground either the G or W terminals [ drawing will show which terminal ] & you get a spark. That is a 50/50 test. No spark, module is bad. Getting spark is good, means module is likely ok, but not a fail safe test, as it does not test the input from a p/up.
Congrats on going to HEI, it is a brilliant design.
 
67Dart,
No problem electrically using the cap shown, but you have to make sure if using in a car engine that the cap can withstand the high[er] operating temp.
 
RogerRamRod said:
When you say you ran a wire from the battery negative to the “module/coil/relay bracket” , do you mean you grounded the bracket that holds the module, coil, and relay, or do you mean that you grounded the module, and you grounded the coil, and you grounded the relay, and the bracket? I’m sure you mean each individual item, but just making sure.
I take it this is a new install, not an HEI that was previously running and now has a no start issue, correct?
The distributor drive shaft wasn’t installed 180° out what is it?
Can you post the wiring diagram you followed?
Click to expand...
Yes it is a new install and Yes I did connect each part of the puzzle to the ground via their own connections. Although wired in a series to the ground it should not matter. I followed FFRC on page 18 of the HEI thread and SSDans info on the build.
 
Also check the pickup in the distributor ohm it out. Usually between 250 and 400 ohms. Those brand moduales are usually the best from the testing I have done on them. Old school Napa tester.
 
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So what HAVE you done? Re-read my post..........Simplify the problem, make CERTAIN it has battery voltage, make CERTAIN it is wired correctly, and then see if it makes spark. If not, it is either something like.......

1...A bad connection in the distributor connector
2...Something wrong in the distributor or pickup
3...A bad coil
4...A bad module

WHAT SPECIFICALLY are you using for a coil? some of the epoxy coils have somewhat "tricky" connections!
 
Thank you all for the help and great drawings. I was able to walk thru it all and did find one loose connector. Also found a problem w accelerator pump so on to that now!
 
"No start" sounds like you have jumped to step 10. Backup to step 1 which is spin the distributor by hand out of the car with distributor cap off. Connect a HV cable from the coil post to ground and clamp a timing lamp over it. Spin the distributor and flash the lamp at the reluctor. If it doesn't flash, check connections and perhaps swap in another module. When flashing, the reluctor teeth should align if correct pickup polarity. If in-between, reverse pickup leads. You can put a spark-tester at the end of the cable ( or just set a gap, or use a spark plug w/ threads grounded) to hear the power of the pops. Watch youtubes. The 8-pin HEI module is better since a cable to the GM coil and has sealed Weatherpak connectors. The HEI mounting screw must be grounded to the same point as the spark plug threads.
 
BillGrissom said:
"No start" sounds like you have jumped to step 10. Backup to step 1 which is spin the distributor by hand out of the car with distributor cap off. Connect a HV cable from the coil post to ground and clamp a timing lamp over it. Spin the distributor and flash the lamp at the reluctor. If it doesn't flash, check connections and perhaps swap in another module. When flashing, the reluctor teeth should align if correct pickup polarity. If in-between, reverse pickup leads. You can put a spark-tester at the end of the cable ( or just set a gap, or use a spark plug w/ threads grounded) to hear the power of the pops. Watch youtubes. The 8-pin HEI module is better since a cable to the GM coil and has sealed Weatherpak connectors. The HEI mounting screw must be grounded to the same point as the spark plug threads.
Click to expand...
I have ground wires in series from battery to module screw to relay to mount (holder for parts) to coil body. I’ll add one to the motor as well. Maybe that’ll help? Thank you.
 
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The main batt cable should go to the engine block. I like to jumper from the block to the body with a "Ford style" starter cable (eyelet to eyelet) about a foot long. Bolt to the rear of the driver side head (look at the front of the pass side head) and then to say, the master cylinder studs
 
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