I put a new HEI distributor from O'Reilly's in my car less than 100 miles ago. New plugs and wires. took the car apart for new radiator, electric fans, serpentine drive. Wouldn't start so we took the module to the store and had it checked, it was bad. So I got another module, had them check it before we installed it. Car starts instantly, no need to give it gas. Drove about two miles and it sputtered and stalled. Now it just spins. Pulled a plug wire and it has a very weak yellow spark, so weak it was dark outside and I couldn't even see it, but my friend could. This was at 9 pm last night. I had the car towed home and haven't had a chance to look at it again yet. Is there anything else I should check?

 

The HEI ignition modules are sensitive to voltage, anything less then 12v and you will have problems. Most replacement modules come out of china now, if you can get and original GM module I would try that next after checking the voltage at the distributor.

 

After I check the voltage, would it be advisable to use an aftermarket high-performance module? I see that Accel, MSD, and Pertronix have them.

 

I suspect you are correct for the recent Chinese parts being sold, but OEM HEI modules are designed to operate correctly down to six volts, so that cars sold in northern climates will still start on frigid winter mornings.

 

No. Find an OEM module (in the junkyard if you have to), and check the coil that's on your distributor. You may have a secondary to primary path/short in your coil that is backfeeding high voltage spikes into your module.

 

Yes, what he said....possible coil problem. Also, I have used the MSD HEI module without problems. This....https://www.summitracing.com/parts/msd-83647

 

What year is the car? If it's a 74 or older I assume assume you have checked to make sure that to make sure that it's being fed from an Ignition wire and not the original resistor wire used for the points distributor points distributor? I have had a couple of these modules fail myself within a short time after converting. I had Both modules from eBay and the local auto store fail. So far knock on wood knock on wood the module that's installed now has worked for 4 years but I carry a spare just in case after being stranded when the last failure occurred.

 

Just curious, with the nation in sweltering heat, you did apply the "Heat-Sink" compound under the modge right?

 

Is AC Delco the OEM manufacturer? I found this locally:
https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds
Didn't they quit making HEI back in the 80s? I am skeptical that I will have good luck with a 40 year old module from a junk yard.

 

FYI
Decades ago I bought a spare 1980 GM distributor from a salvage yard (non-tach-cable drive) AS A SPARE.
I have an aftermarket cable-tach drive distributor for thr last 7 years.
13 Volts to the dist. and still had two Module failures in seven years.
All other components in the dist. test perfectly. Ohm meter shows the dist. housing has perfect ground to the engine.

I can install the (non-tach-drive) GM1980 HEI Dist. and the car starts/runs/cruises perfectly...IMAGINE THAT.

 

The car is a '74 with a non-original, modified small block. This engine is a replacement of another non-original, not stock small block that was in the car when I got it, which threw a rod the day after the fresh paint job. It still had a tach-drive distributor, and an Alison points eliminator. We installed that distributor on the engine Duane and I built, and I drove the car around town and on a few 15 mile trips to work and back. The ignition failed and stranded me, so I got a F.A.S.T. points eliminator to replace it. I may have installed it wrong because the car still wouldn't start. In desperation, we put a new H.E.I. setup from the parts house, the day before a car show. I drove it very little after that before tearing it down to do the radiator, fans, serpentine, etc. Duane did put the heat compound on it, he did verify 12 volts, and the old wire with the resister was still in place but had been taped off.

The car has been used and abused for likely most of it's life, but was a running driving car when I got it. I am slowly rebuilding it. It had MANY paint jobs and half-*** repairs that were discovered when we stripped it to bare fiberglass. The wiring is a mess, it will all eventually be replaced as we go through the car. I don't want to dismantle the entire car, I want to have fun with it as we rebuild it.

 

I've had countless G.M. vehicles with HEI, especially back in the 80s when I started driving. Changed plenty of caps and rotors. I wouldn't swear that I never changed a module, but I don't remember doing it. I didn't even know what it was when Duane told me mine was bad. I haven't done much mechanic work in the last 20 years or so until now, maybe I had failures in the past, the 'ol memory is definitely failing though!

 

Well, how's your luck been with brand new parts out of a shiny box?

AC Delco is a marketing group at GM. They buy stuff from all over the world and stuff the parts in AC Delco labeled boxes. Do not infer that the parts in those boxes necessarilly have any relationship to OEM parts or involvement with GM design and manufacturing engineers. GM sold most of their component divisions in the late 90s, but kept the rights to the AC Delco name, which they print on boxes, and as I said before, stuff with parts from all over the world.

 

Richard,
I read your story.
I hear your frustration.
I feel your pain.
I raise my glass and toast to your determination.

Some day, it will all be worth it.

 

Exact same scenario with my 74 which also had an original distributor with an old point elimination kit I swapped for a $60 china tach drive unit when I replaced the original l48 after driving it home. Besides the module failures the distributor has been fine but I did buy a recurve kit and swapped the springs to get the advance to come in earlier. I swapped my originl 84 c4 coil in while troubleshooting the first module failure but the coil was fine as it turns out anyway. and in my case I DID use the heat sink compound. GM never made these modules as far as I know.. they were contracted by an oem supplier I believe like most of their parts are. Ironically the module thats lasted for 4 years now was nothing special. just a cheap replacement from the local advance auto.

 

Wow I did not know that. Cheap China crap with the Delco name, ain't that great? I wonder, how would I be able to tell if a module from a boneyard was OEM, and not replaced with the same crap I have now sometime in it's past? I used to get parts from the junkyard all the time, 30 years ago. But never electrical parts, as a rule. Always got that stuff from the store or dealer. Of course, that was back when we still had an industry in America...

 

on a separate unbut somewhat related note... Has anyone had issues finding quality points as well these days? I have an old harley golf cart I fought with for months because all the points I bought were poor quality trash... ended up finding some new old stock points for a ford truck that fit and worked well but I read on the golf cart forum (Yes, theres a forum called buggies unlimited) that many of the coils and points sold now are very poor quality for these old carts. I mention this because I fear its just the nature of the beast with these older machines as we move further and further towards a more disposable economy.

 

besids ac delco, the Delphi companies have also been sold off.. I believe the guy that owns federal mongol owns it now but their items are also sub contracted overseas and to mexico depending on what it is. Same goes with most of the big name auto parts companies that honeywell bought out. Theres big money in buying these big companies with good old reputations and eventually closing all manufacturing down while selling foreign crap at the same higher prices the real products used to demand. Timken is another company that no longer makes thier automotive products but at least they have them made by a large well known japanese manufacturer. Even GM does this. My friend used to work at the former harrison radiator plant which became delphi... 10 years ago GM pulled a stunt so they could buy thier radiators from china, all the while they still owned the delphi plant in lockport and the employees paychecks continued to come from GM. But on paper GM didnt directly own them anymore so delphi made radiators for the foreign car companies that actually made car in the states with american parts like Honda.. The Irony that my 2007 Honda Ridgeline was the most american made truck of 2007..

 

Lee did put a recurve kit in there. I just heard from Duane, he mentioned something about the motor mount being loose and that's where the ground strap is. Could a poor ground be the culprit?

 

And I raise mine to you as well sir, along with all you guys here giving me advice. It is worth it, even though I have a long way to go, every time I fix something and I get in this thing and bang through the gears! Sometimes I wish I could just drop it off at a shop with a blank check, but I'm just a poor boy. There is satisfaction in being hands-on in this project. Luckily I have good friends and family, and the great help from the sharp guys on the forum, or I'd never have what I have dreamed of for nearly half a century-my own Corvette.