Update on my Ignition Module failure!

[MikeB]

Hemmings Motor recently had an article on HEI distributors. They stated that the red rust colored dust we see on the advance weights and surrounding areas, is from mis-placed electrical sparks. The article is available on their website.

https://www.hemmings.com/stories/tech-101-how-to-cure-the-hei-mystery-misfire/

Good info. I had never heard of the problem and would have guessed that if the coil secondary winding (output) was open due to a bad or missing plug wire, then there would be 12 volts on the primary winding, but none transferred to the secondary winding when the primary winding "collapsed" to zero volts. In other words, no path for current. But I can see how the secondary might find one, even if it had to arc.

Amazing to me that with all the potential HEI problems, many of us have never experienced any, at least not any that killed a module.

 

[hack_man]

So what's the safest way to disable ignition if you want to crank the engine without it starting? Pull the electrical connector plug on the side of the distributor?

 

[Ricko1966]

So what's the safest way to disable ignition if you want to crank the engine without it starting? Pull the electrical connector plug on the side of the distributor?

Yes

 

[Craig Nedrow]

Yeah, I have run points, and while I still have engines with points, like the much hotter spark of electronic ignition, Pertronics has been good, but I run MSD on all my small and bbc engines. Yes I have a brand new one in a box I bought from ebay, it did not work, but could be sent back to be fixed. I buy American companies, as you can call them, and most are very responsive. I also run the Pro Billet dist., as well.

 

[hack_man]

Why is the MSD unit so much larger than an OEM HEI Ignition module? I know heat sinking is important but the size difference is huge.

 

[PrairieDrifter]

Why is the MSD unit so much larger than an OEM HEI Ignition module? I know heat sinking is important but the size difference is huge.

The street fire should be the same size module as factory gm. All of the other msd stuff is all ignition box controlled which mounts on the firewall or similar.