Lotta bad parts floating around nowadays: HEI modules

[jumpsoffrock]

So from what I've read bad HEI modules are nothing new, it was a problem a long time ago too, but worse nowadays.

I am getting a Cadillac 500ci engine prepped and ready for installation in a project and I wanted to use HEI, so I bought a "remanufactured" HEI bare distributor--which means it came with the metal housing, the advance mechanism, the module, and capacitor.
Sadly they are NEVER in stock and I waited for a month before it was even available. Back on rockauto today, they're still outta stock.

I had to supply my own rotor, cap, coil, and coil cover.

Put it on the engine and it was not firing, I saw no reason why, so I checked for spark and of course: none.

After learning about how to diagnose HEI and fiddling with it for a couple days, I discovered the brand new module in the rebuilt distributor I just bought was rotten, bought a Standard LX301 and the engine fired right up(as well as it could with a junkyard carburetor sitting for 10 years in my garage).



So as far as I can tell here's a list of things that have been talked about on various forums that are apparently failing when brand new or just breaking in. And also where I heard it from

♦HEI modules. Here and in personal experience.

♦Ring/pinion sets for differentials. This forum and a Ford truck forum(across models ranging in age by 50 years; sounds like everyone is feeling this)

♦Camshafts(and lifters?) Every forum I'm on.

♦Quadrajet accelerator pump sealing rings. This information is plastered all over Cliff Ruggles forum--but I haven't experience this yet myself and as nice and approachable as Ruggles is--he responds himself on his forums--I am a bit suspect being that he and many other qjet gurus sell their own accel pumps that are "resistant". Bit of a conflict of interest, but I guess I'm about to find out.


I don't mean this to be a "china bashing" thread. China makes rockets and surgical tools and computer hardware/software as good as anyone else does.

China will make anything we ask them to make for our cars--and they'll make it as good as we're willing to pay for.

Why is all of our "chinese junk" so bad?


hobbyist consumers.


They can't sell a "as good as factory GM 1969" electric window motor for a camaro, becaus it'd cost $380 a piece. So they make it good enough and sell them for $80-120.

They can't make C10 fenders as accurate as NOS and sell them for $800 a piece; so they make 'em good enough and sell for $150.

I guess we just gotta watch out for eachother and post our reviews. I have a 1 year warranty on my distributor, but I didn't wanna wait 3 months and pay shipping. I bit the bullet, payed $47 for a module at oreillys and went along with my life.(yes I checked, the module from rockauto woulda been $34 shipped and taken half a week)


end rant...

[1970-CST]

And China is knocking off just about everything. Amazon is a 50/50 crap shoot for AC-Delco, etc. I had a set of NGK plugs that I could tell were knock offs. Ohmed out all over the spectrum. Junk. Had a water pump purchased off GM parts direct for an LS engine last 1.5 years, growled and leaked. GM OEM knock sensor for my wife's traverse last 3 months. 3800 Buick engine needed a coil pack. Parts store brand lasted 6 months.

GM is OK with it, there products as well as others have been junk for 25 years. I have a 1992 full size blazer, 350 TBI motor. 350k plus miles on original transmission and engine. Intake has never been off. Did a distributor and timing chain at 275k miles out of "probably should". 1 water pump and 1 starter. My Lesabre has 250k plus miles and it just keeps going. My wife's 2017 traverse it's always something. 150k miles and it's had 3 knock sensors, engine mounts, trans valve body, ac compressor, trans cooler to keep the trans alive, suspension bushings. Never ends.

[mr48chev]

With a lot of pieces it has been that way for quite a while. It used to be that you could get Napa Echlin modules and they were as good as the ones straight from GM but now you never know where they were made.

I've got the Napa HEI trouble shooting pages on my Mr48chev photobucket page but this computer is too slow to get the link.

[Rust_never_sleeps]

Pertronix makes modules for GM ignitions. You might have better luck with those

[tim_mc]

Yep, Pertronix, or Davis Unified Ignition modules perform better than stock. The DUI modules have worked well for me:
https://performancedistributors.com/...ories/modules/

[raggedjim]

I can attest to the accelerator pump seals. I rebuilt mine twice and had bad performance, it would be fine after rebuild but gradually get worse, turned out it was the seal on the accelerator pump. I think the ethanol in the gas was eating the seal after a period of time.

I did end up getting a new seal that was rated for ethanol use, it was about 5 years ago so I don't remember where I got it.

[Rich69shortfleet]

Originally Posted by tim_mc

Yep, Pertronix, or Davis Unified Ignition modules perform better than stock. The DUI modules have worked well for me:
https://performancedistributors.com/...ories/modules/

I was going through a module or two a year. After a put in a Pertronix module about 3-4 years ago I haven't had a single problem.

[DeadheadNM]

At least as of a year ago or so NAPA HEI modules were USA not Peoples Republic of China made.

[Rust_never_sleeps]

Originally Posted by raggedjim

I can attest to the accelerator pump seals. I rebuilt mine twice and had bad performance, it would be fine after rebuild but gradually get worse, turned out it was the seal on the accelerator pump. I think the ethanol in the gas was eating the seal after a period of time.

I did end up getting a new seal that was rated for ethanol use, it was about 5 years ago so I don't remember where I got it.

I got a blue seal on the first rebuild that was ethanol "resistant" and it was turned into a ruffled skirt by carb cleaner :shrug:
I just source them from Cliff's now...and I go easy on the carb cleaner

['68OrangeSunshine]

I Keep a spare Module in the glovebox of both trucks.