68 Newport wiring harness research

Biggredd2069

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I have a couple of gremlins in the system. I'm trying to modernize some and I have a lot of extra wires and stuff. I have a headlight relay, upgraded alternator, modern stereo with 2 amps and subs, electronic efi, etc. The gremlins I had are 1. I have a parasitic drain from something I can't find yet so I have a battery ground disconnect switch. 2. I have a loose wire somewhere in general and sometimes my car won't start unless I go jiggle some wires. Very frustrating. And 3, likely related to 2 is sometimes the car will start and the battery won't charge. Likely a loose wire. I even have the alternator direct to the battery linked. Just happens occasionally. I have not read good reviews about the painless wiring kit and I don't necessarily want to go down that route. Is there a kit that just replaces that bulk head in the engine forward and leave the rest of the wiring intact that gets rid of the ammometer wire? (I probably misspelled that). But I just want to update the engine wiring only long story short. 68 Newport 383.

Also, I have a 67 Newport grille and wheel side skirts for sale
 
Yes there is!

I came across it online last year. Do I remember the URL off the top of my head? No.

I found it using google.

I’ll look too and post it when I find it unless you post it first.
 
There is no shortage of results for a-body and Chevy. I've searched but not sure I know what I'm looking for unless it jumps out and bites me.
 
Thanks guys. I see the one says efi conversion work a points distributor. I have a pertronix flame thrower 2 electronic ignition. For the standard one on herbs are those just direct replacements or do they get rid of the bulk head at the firewall? I mean is there any issue keeping it and just replacing? I just need a refresh if nothing else.
 
I'm just going to make a guess here. Looking at the part number on Herb's it starts with EWH. I cannot help but wonder if EWH stands for evans Wiring Harness. They are in Erie, PA. They maybe able to offer you additional assistance.

As far as the bulkhead goes if it's clean (no corrosion) and not damaged by heat or anything else I would leave it. You've done the ampmeter bypass and headlight relays so the you have lifted the high amperage load from passing through the bulkhead.

What wires are you wiggling? Under the hood or under the dash?
 
Thanks guys. I see the one says efi conversion work a points distributor. I have a pertronix flame thrower 2 electronic ignition. For the standard one on herbs are those just direct replacements or do they get rid of the bulk head at the firewall? I mean is there any issue keeping it and just replacing? I just need a refresh if nothing else.

I would email or telephone and ask them.
 
I'm just going to make a guess here. Looking at the part number on Herb's it starts with EWH. I cannot help but wonder if EWH stands for evans Wiring Harness. They are in Erie, PA. They maybe able to offer you additional assistance.

As far as the bulkhead goes if it's clean (no corrosion) and not damaged by heat or anything else I would leave it. You've done the ampmeter bypass and headlight relays so the you have lifted the high amperage load from passing through the bulkhead.

What wires are you wiggling? Under the hood or under the dash?

Here’s the link to Evans.

EvansWiring.com : Product Catalog
 
Thanks, I'll give them a call. For clarification i don't know which wire i have to wiggle. I get no attempt to start at all, then mess around and still no start, wiggle some more stuff and it starts. Happens just occasionally but more frequent than is acceptable. Time to get er done.
 
Where are you moving wires at though? Under the hood or the dash?

You might have a loose wire at the ignition switch or a broken wire in the harness.

Intermediate problems are a challenge to find.
 
I spoke with Evans wiring. Probably just gonna buy the new wiring harness for the engine bay. Can't hurt to update and it's only about 165 total. I did have some issues with the fusable link a couple years back so maybe a refresh is due.
 
as far as parasitic drain...hook a 12 test light between a disconnected battery cable and battery terminal...if it lights up you have a drain...start pulling fuses and disconnecting things till it goes out...(make sure dome light is off or the open door will send you on an unnecessary chase)...alternators with bad diodes can also drain the battery while appearing to charge normally...a light that flashes for a second then goes very dim is powering up the capacitor for a stereo's memory and is a normal low amp draw...make sure stereo amp isnt hot all the time...some need relays triggered by the radio to turn them on and off....when you say no start...cranks the starter but no ignition or wont even crank the starter?....i had a crank but no fire that drove me nuts wiggling wires and it turned out to be the module inside the distributor...factory electronic... I come from the vw world and the standard over there is anyone with a pertronix conversion either carries points and condensor or a spare distributor cause their reliability is less than spotless
 
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I assure you I've done that to exhausting levels and I get absolutely no where. Don't have time to list the details of what I did but I promise I've spent a ton of time on it
 
Cars of this era didn't have sealed electrical connections and they go bad frequently. If you go to delcity.net you can buy the parts to rebuild your wiring. Look for Packard 56 connectors. They have terminals, wire (not exact factory style but close enough.) and butt splices. I've found the bulkhead connector is the most frequent culprit.

Order a bunch of male & female terminals for various amperages (you don't need many high current ones) and start replacing the wires one at a time. I should mention there's a good chance the problem is on the firewall side. So be prepared to be a contortionist and work under the dash splicing in new terminal ends. A service manual will help with determining which wire is the likely culprit.

I use a butane mico torch with butt splices and heat shrink tubing. Avoid the crimp on stuff, it is unreliable. Soldering is 100% reliable if done properly. A set of jewelers screwdrivers is useful to get the terminals out of the housings. if you look closely at the engine compartment side of the firewall connector you will see a small hole above each terminal opening, stick the smallest flat blade screwdriver in it and twist while pulling on the wire from the back side and they will come out easily. Just be patient. I found it's best to disconnect all three connectors and depress the clips that hold the connector to the dash to push it inside the car and work on them there. Removing the drivers seat makes it 1000% easier to do all of this. The male terminal ends can be removed with a decent pair of needle nose pliers, squeeze them and pull them out from the back side. You will see what I mean once you have new terminals to look at.

Delcity does have a few housings but not all of them so be careful when disassembling things. Usually the housings can be reused unless they are in really bad shape. I have seen the firewall ends on ebay before too.

Don't remove all the wires at once, it will be very difficult to remember where they go when reassembling them. Do one at a time and it will go smoothly.

If you can get a hold of a small stiff brass brush you can clean up the low current male terminals instead of replacing them. Welcome to a long weekend project.
 
As for the not starting issue, what does that mean? No starter action? Starts an dies when you let off the switch? Cranks and not firing up? There really aren't a lot of electrical issues that can cause this. Not cranking is usually related to the starter relay and associated wiring. Cranking and no ignition has a couple wiring paths, the IGN2 path from the ign switch to the ballast resistor and coil. Also the distributor and coil could be an issue with the coil or points/ distributor. Starting and dies is the IGN1 circuit from the switch to the ballast resistor + ballast resistor. But if it starts and runs sometimes that rules out the coil and points unless there is a loose connection. So really there is only three wires going through the firewall involved. But a remote possibility is the fusible link as you mentioned. If it cranks the fusible link is fine.

I would start by connecting a voltmeter to the coil high side and see if you have voltage during cranking and when the switch is on. Measuring nothing leads to the wiring going back to the firewall connector, back to the switch and battery connection. Only two wires and a ballast resistor here. If you have voltage and still won't start, look at the coil/points etc.
 
I guess I should preface about checking the electrical that I've done all I can within my means. I try to act like I know what I'm doing but truth is in learning as I go so it's not always smooth sailing and I prefer to try and do a lot of it myself if possible then pay a professional to fix my bigger mistakes. But as for it not starting the lights still come on, I'll turn the key to start, And nothing happens. As in the motor doesn't even attempt to turn over. Just silence and no action. I had the engine rebuilt about 2 years ago, I have a pertronix flame thrower 2 ignition. Fitech 400 fuel injection, 60 or 65 amp alternater, and a new short style starter. I have been in talks with Evans about one of their engine bay wiring harnesses just to eliminate a whole section at once.
 
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