Gen 3 HEMI electrical problem

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gtxclone

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i have recently installed a new crate hemi in my gtx i'm using the 727 and i have the new harness from chris squire i have all the connections made but im at a loss on what to do with the old wiring in the car i need info on where to run the new alternator main wire and what to do with the neutral safety switch wire from the unused solenoid relay also can anyone give me a sketch of the other old wiring and where it should go thanks for any help you can provide please pm me if you can Can anyone help please
 
Assuming you are going to install a late model high output alternator you will need to bypass the factory ammeter meter. The bulkhead connection and the ammeter will not carry the 100+ amps that a late model alternator puts out.

The Gen III Hemi has three wires. One thick red wire (I believe it is 4 gauge) should be run to the positive post on the starter. The other two thinner wires can be run to a standard factory chrysler regulator that your car came with. The two wires are interchangeable, one goes to ground and the other connects to the regulator. Beware, it is critical that the housing of the regulator has a good ground or your charging circuit won't operate properly.

Attached is a diagram for the alternator. Can't help you with the Neutral Safety Switch, I'm running a 4-Speed.

Regards,
Joe Dokes
 

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The NSS should hook up just like it did originally. Your starter relay should look something like this:

The "start" wire from the key, that is, the original, goes to either of the two push on terminals at the top of the photo. The remaining push on terminal goes down to the center terminal of the NSS on the 727

mopar-53-54-55-56-57-58-59-imperial-starter-relay-new_170579962271.jpg
 
hey thanks guys i appreciate the info i have a new harness from chris squire it has wires that go to the slternator but the big cable isnt there so the information on where to put the big wire is helpful thanks joe and thanks for the info on the neutral safety switch i wish there was some diagram of every wire both new and old that would be very informative thanks again if you know of any other wiring stuff i can use please let me know
 
its a 67 belvedere that i am cloning like a gtx ive got a crate 5.7 and a rebuilt 727 and using chris squires wiring harness and an alterkation front end
 
OK, probably the closest I could get to steering you to a factory manual and diagram is over at MyMopar you can download a 66 shop manual. The page numbers in your viewer will be sequential, and don't follow the Mopar "dash" system, so you'll have to play with them:

http://www.mymopar.com/index.php?pid=31

The link:

http://www.mymopar.com/downloads/servicemanuals/1966_Plymouth_Service_Manual.zip

Section 8, electrical, starts page 189. Wiring diagram index is page 289

The main diagrams you need are 290, 291 engine bay and instrument panel.

Sometimes easier to follow, l but not as complete are the MyMopar diagrams:

http://www.mymopar.com/downloads/1967/67BelvedereA.JPG

http://www.mymopar.com/downloads/1967/67BelvedereB.JPG

Of course IF you are using the 70/ later style regulator, that part is different. You CAN ground one of the field terminals of your alternator, and use the 69/ earlier style regulator, and you can get them in modernized solid state replacements as well.

Do you have an online link to documentation for the harness you bought?

I didn't realize you had a GTX that old, so if you have an early 727, it may only have 1 NSS terminal instead of three. The outer two on the later transmissions are for the backup lights. On your car the backup light switch is on the 4 speed, or if auto, on the linkage, column, or console shifter.

One thing that would probably help is to identify what you can, then post photos or at least details of what color wires and what they are near of what you have left.
 
thanks i have the factory manual with those diagrams but im confused on what to do with the original wires that are being replaced by the ecm i think i need to simply determine which wires are no longer needed thanks for your help this is a great place to learn dan
 
Doesn't the harness come with docs on how to hook it up? Can you download this online?

I found this, could not get it to load.................

http://hotwireauto.com/
 
well actually i didnt get any docs with the harness i phoned chris several times asking about where each wire went (they were labeled) but it didnt show any diagram except the truck engine that you found online and it didnt tell you anything about what to do with the old wires that were left from the old engine im not a wiring guru by any means and it seems like for 2400 bucks you should get a book manual or something to tell you what each wire does and what function it replaces all i got was a box of wires and a kiss
 
Well if you can post the wire labels which you cannot figure out, I'll be glad to try and help you.

I'm assuming you know and have hooked up all the EFI side of stuff, IE ignition, trigger, injectors, sensors, etc, and now just need to interface it to the body wiring.

A agree for that kind of money, there should be a well written book on the thing.
 
Dan,

Cant help but in the same boat... Im gonna start wiring my FAST controlled HEMI soon, and have to take out what I dont need from a new Ron Francis Kit... So your questions are helping me too.

Post some PICS of that '67, I miss my Belve BAD!!!

JOE
 
here are some pics of my honey hopefully i will get her running again soon thanks to you guys for the great help
 

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wow guys now i feel better hearing that from all you folks makes me think im headed the right way thanks
 
Small question -

Advice provided says
The other two thinner wires can be run to a standard factory chrysler regulator that your car came with. The two wires are interchangeable, one goes to ground and the other connects to the regulator.
Click to expand...

I understood one of the two field wires went to reg (F) and the other went to Ign 12V as per the diagram at the top of the thread?

Can someone clarify?
 
ok guys here is the next question for you the new harness for my hemi has two wires that go under the dash to the starter switch one says (ign switch run/start position) the second says (ign switch start position) does anyone know the color of the original wires for these positions on the starter switch thanks again for any help
 
Rat Patrol said:
Small question -

Advice provided says

I understood one of the two field wires went to reg (F) and the other went to Ign 12V as per the diagram at the top of the thread?

Can someone clarify?
Click to expand...

He has a 66. If he is going to use the original 69/ earlier regulator setup you'd ground one field, hook the other to the original green Field wire.

If he is going to convert to the 70/ later regulator, he'd connect one field to the old green, and wire that green to the new regulator. Then he'd add one new wire (light blue) from the second field connection up to the regulator IGN terminal which is indeed switched 12v or "ignition run"
 
gtxclone said:
ok guys here is the next question for you the new harness for my hemi has two wires that go under the dash to the starter switch one says (ign switch run/start position) the second says (ign switch start position) does anyone know the color of the original wires for these positions on the starter switch thanks again for any help
Click to expand...

Referring to the 66 manual that is posted at MyMopar:

http://www.mymopar.com/downloads/servicemanuals/1966_Plymouth_Service_Manual.zip

and page 290, 291

(Actually this drawing is my 67 Dodge manual, Coronet:)

Now there IS NO single wire that is hot in start/ run. This is just how Mopar switches work.

MY FIRST question is, do you have an ignition which is NOT using the ballast resistor? IF so this solves the problem, as the brown "IGN2" and the dark blue IGNITION will be jumpered together under the hood when bypassing the ballast resistor. This is necessary because the IGNITION (dark blue) goes COLD in "start" and therefore you still need the brown to provide IGN power during crank.

So on the diagram, and assuming you have bypassed the ignition, you can splice into the dark blue. The only place the dark blue originally goes is through the bulkhead to the ballast and the regulator IGN terminal, and to power the cluster

If you ARE going to use the ballast in your ignition system, you'll have to install a diode or a relay to solve the problem

The START wire you would splice into the YELLOW "STARTER" wire. The rear of your switch should look just like this one.
 

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according to the hotwireauto the ecu completely bypasses all the devices on the firewall and utilizes the starter switch to provide the necessary functions just need to know where to attach the two wires they provided and i think by combining the blue and brown wire and utilizing the yellow wire from the bulkhead i can do that
 
If he is going to convert to the 70/ later regulator, he'd connect one field to the old green, and wire that green to the new regulator. Then he'd add one new wire (light blue) from the second field connection up to the regulator IGN terminal which is indeed switched 12v or "ignition run"
Click to expand...

No problem and thx.............I'm good to go.

Thx OP for the chance to clarify.
 
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