Have a HEI in my 70 W30. This is the third time the modal failed, in about a year.each time. Probably less than 200 miles each time. Went to go the local car show,once a month, so was a month ago when I started it. It is a Standard 5 year warranty, is one year old. I bought it from Rock Auto, and to warranty it, have buy a new one then return old one for credit. That's not a real problem. Have you guys had trouble, with Standard unit? Also, when I was checking out it had a note,saying coil should also be replaced. I never saw that before. Is that maybe why I'm burning out my units? Any input?

 

Sorry for double post.

 

I bought the same one from Rock Auto 2+ years ago and no issues. However, I did change the coil too at the time since it needed it and I was rebuilding the distributor anyway. One thing I also did that may have helped too was buy some premium thermal paste / compound and put it underneath. They say it's better than the dielectric grease as it helps keep it cool.

 

Are you using THERMAL paste, and not dielectric grease? There is a difference.

Measure the resistance of the primary side of the coil. If I remember correctly, primary coil resistance is around .5 ohms. If it’s less than that, replace the coil.

 

Those HEI modules are all pretty much trash nowadays. I keep a spare in my glove box and have changed it on the side of the road more than once. I think I should change the distributor eventually.

 

Matt69, Where do your buy the Thermal Paste from?

 

x2 on keeping a spare. I only go with NOS D1906 modules for my cars, and I always have a spare in the trunk. These things croak suddenly leaving you stranded if you don't have a replacement. And this is not something readily stocked at auto parts stores.

 

I would suggest adding the coil ground. I'm honestly not 100% sure if it's necessary, but it certainly can't hurt and has to be a better ground than the distributor base.

 

Module failure can be caused by AC in the voltage supply, undervoltage/overvoltage at the distributor, spikes from a mechanical VR, and too large of spark plug gap also.

 

Before I went to Progression Ignition HEI (bluetooth controlled), I had good luck with Taylor brand HEI with the traditional weights and springs. If you're curious about Progression Ignition HEI, see my post elsewhere here on C.O.. Short version is they do special stuff and have lasted well thus far.

And yes in the Taylor years I kept modules in the glove box like everyone else. The modules fail catastrophically without warning and will leave you by the side of the road happily. My conclusion is if you're going HEI, get a good brand like Taylor or MSD. If you can avoid offshore products you're ahead of the game. The low end stuff is just junk from what little I know.

Haven't had a problem in 2 years or so with the Progression HEIs in my 2 big cars. They get regular use, not quite daily, but at least a couple days a week when the weather is good.

Cheers
Chris

 

Any electronics or computer store will more than likely have it. If not, I think you can buy it at Napa.

 

I use ACDelco "old school" modules only in HEI. Haven't had to replace one. Ever. But I have several spares. Don't go over 0.060" on plug gap, and ENSURE you are using the correct polarity pickup coil and main coil. Extra grounding never hurts, and battery supply 12V to the distributor and you should be good.

You can use either the thermal paste under them, or the little packet of grease that comes with the Delco units. When replacing, you do not have to clean and re-apply the thermal paste if you can smooth out a thin film of what's left when removing the dead module. You can if you wish, but not necessary.

 

I’ve been using HEI’s for a long time. Totally agree that .060 is too large a gap. I typically run .045”. Grounds are super easy to add and highly recommended. If you can find Delco OEM units, they’re the ones to use. Or get a bunch of latter day replacements. And stash a few in the glove box/trunk for replace-ability. And don’t forget to stash the tools you’ll need to replace the modules.

Cheers
cf

 

Save yourself a lot of trouble and get a points distributor like a real W-30 should have.
Slip a set of points in every 10,000 miles or five years and don't worry, be happy.

 

x 2

 

I'm pretty sure the only tool needed to change the HEI module is a Philips screwdriver (and maybe a roll of shop towels and extra thermal paste).

 

[QUOTE=442Harv;1615165Also, when I was checking out it had a note,saying coil should also be replaced. I never saw that before. Is that maybe why I'm burning out my units? Any input?[/QUOTE]
Back in the day when I was repairing these cars on a daily basis we found that a bad module could easily damage a coil, and vice versa.
When a car came in "on the hook" we changed both the module and the coil,
Also we found a lot of problems with poor or intermittent performance, and sometimes failure, attributed to the Pole piece.
Not the pole piece itself so much, but the tiny wires that go to it.
They flex every time the vacuum advance works and can easily break inside the wire.

 

This was exactly the issue with my black/silver 79 Cutlass, as it turned out the wires in the pick-up coil were bad due to the flexing by the vacuum advance, causing a break/hesitation which I mistook for a vacuum leak. An NOS pick up coil fixed the issue. In fact I'm now suspicious I have the exact same issue with my blue 79 Calais, slow acceleration is fine but if I accelerate harder I get a distinct hesitation and then the car springs to normal acceleration.