'64 Dart 270 Wiring

Ok I'm going to try and use this time sheltering in place to get as much of the work on my Dart done as possible.

My wiring is... bad.

A few disclaimers: There are non-stock speakers in the rear (none up front of course), non-stock radio, and there is an air conditioner under the dash. At present, the air conditioner is hooked up to some sort of pump with a hose going to said pump from the radiator, and then a hose to the air conditioner, but there's what appears to be a ground cable from the A/C not connected to anything, but I believe the positive cable is.

Aside from that, just about everything is stock. I have a rebuilt alternator, not sure what the amperage output is from that, and just recently had to get a new alternator cable put in as the other one had burnt up.

The underdash harness is in bad shape. The previous owner opted to bypass the fuseblock and not install any kind of fuse when installing the new stereo system. Lots of cable is just wrapped in electrical tape and ziptied there, and nothing is going through the fuse block. Currently, only my ammeter gauge works. My fuel gauge is touch and go, seems fairly accurate, but not totally. Nothing from the temp gauge (it's not even hooked up on the back), and the lamps aren't connected.

What should I do? A replica harness from Classic Industries is around $650 which is insane. I had hoped to do a switch from the stock fuse block to a modern blade-style, and found a Mopar restomod wiring harness where that had been done, for a little over $500.

Or should I scrap the idea of buying a built harness and construct one? I have enough electrical knowledge to wire everything I think. Should I just wire everything by hand, attach it all to a modern fuseblock, use the factory recommended fuse amps, and then go with whatever would be recommended for the current stereo (as opposed to the 7.5A factory for the original stereo)? Or should I use heavier wire?

Any advice, links, references, etc would be greatly appreciated!!

chinze57 said:

Or should I scrap the idea of buying a built harness and construct one? I have enough electrical knowledge to wire everything I think.

Click to expand...

based on what you've written, I'd say you could with some studying and planning. At least a couple areas of understanding will go a long way up the learning curve. Then you could build your own. Slightly easier may be salvaging what you have. For that part, remove everything and tack it to a big plywood board.

chinze57 said:

Should I just wire everything by hand, attach it all to a modern fuseblock, use the factory recommended fuse amps, and then go with whatever would be recommended for the current stereo (as opposed to the 7.5A factory for the original stereo)? Or should I use heavier wire?

Click to expand...

Choose wire size based on load. Find out what the max power draw can be (in Watts). Then calculate amps based on max voltage. Us 15 V to be on the safe side. Most items draw more current when supplied at high voltage.
Choose fuses based on smallest and weakest wire or connection.

chinze57 said:

The underdash harness is in bad shape. The previous owner opted to bypass the fuseblock and not install any kind of fuse when installing the new stereo system. Lots of cable is just wrapped in electrical tape and ziptied there, and nothing is going through the fuse block.

Click to expand...

Well maybe there's enough to salvage. Laying it out on the board will give you the lengths and let you replace the wires one by one. This assumes they haven't all been snipped. short. Since its running I'm hopeful it will at minimum be a guide.

chinze57 said:

Currently, only my ammeter gauge works. My fuel gauge is touch and go, seems fairly accurate, but not totally. Nothing from the temp gauge (it's not even hooked up on the back), and the lamps aren't connected.

Click to expand...

The ammeter is not like other gages. It's big flat copper bar with a stud on each end. Current flowing through the bar moves the needle. Current flowing to the main splice moves the needle toward discharge. Current flowing into the battery moves it toward charge. When the battery is charged, there's no current flowing through it.

The rest of the gages work from a points operated voltage limiter. Clean everything, and check that the limiter's connections on th ecircuit board aren't broken. These gages work by heating a bimetal in the gage. Each gage is connected to the sending unit which is a variable resistor to ground.

chinze57 said:

Aside from that, just about everything is stock. I have a rebuilt alternator, not sure what the amperage output is from that, and just recently had to get a new alternator cable put in as the other one had burnt up.

Click to expand...

That's bad but could be worse. Alternator output carries the highest current load of all the wires. When the engine is running it not only powers the usual stuff, but also recharges the battery. If the battery is low, that can add a lot of current at least for a few minutes. Stock alternators generally maxed out at low rpm which helped protect the wires a bit even when the battery was heavily discharged.
Current out depends on the what the demand is. What you could measure on a machine or with a Volt-Amp-testor on the car would be maximum potential output at a given rpm.

'64 should have an fusible link.
Fusible Links in Charging Systems with Ammeter

To make new terminal connections, you'll need Chrysler type connectors and an open barrel crimper.
Do a search here for that info.

Consider this: by the time you buy dozens of differently colored/striped rolls of wire, in a half dozen different gauges; dozens of different terminals and connectors (some of which are a pain to find), the fuse block, solder/heat shrink and a GOOD soldering gun; spend who knows how much time measuring, fitting, wrapping and routing wires; suddenly $500-600 doesn't sound too bad for a pre-made, custom fit, factory terminal, ready to go harness that you can put in in a couple of evenings. It can be done, but your time is worth something, too. Only you know for sure.
Or if you're still really bucks down, post a wanted ad here and see if you can score a decent original.

To do this on the cheap will mean a lot of work on your part. If you are willing to invest the time, you can repair what you have. I agree with first post that you should completely remove the dash wiring harness to lay-out and inspect. This will mean you will need to remove the gauge cluster and radio. Removing the column or at least the steering wheel will give you more room. This loom runs from kick panel to kick panel and to the bulkhead connecter. When removed lay it out and begin identifying and marking each connecter using the FSM. Now you will begin to see what is good and what needs repair. Your choice- do the work or pay the $600.

Mattax said:

based on what you've written, I'd say you could with some studying and planning. At least a couple areas of understanding will go a long way up the learning curve. Then you could build your own. Slightly easier may be salvaging what you have. For that part, remove everything and tack it to a big plywood board.

Choose wire size based on load. Find out what the max power draw can be (in Watts). Then calculate amps based on max voltage. Us 15 V to be on the safe side.
Choose fuses based on smallest and weakest wire or connection.

Well maybe there's enough to salvage. Laying it out on the board will give you the lengths and let you replace the wires one by one. This assumes they haven't all been snipped. short. Since its running I'm hopeful it will at minimum be a guide.


The ammeter is not like other gages. It's big flat copper bar with a stud on each end. Current flowing through the bar moves the needle. Current flowing to the main splice moves the needle toward discharge. Current flowing into the battery moves it toward charge. When the battery is charged, there's no current flowing through it.

The rest of the gages work from a points operated voltage limiter. Clean everything, and check that the limiter's connections on th ecircuit board aren't broken. These gages work by heating a bimetal in the gage. Each gage is connected to the sending unit which is a variable resistor to ground.


That's bad but could be worse. Alternator output carries the highest current load of all the wires. When the engine is running it not only powers the usual stuff, but also recharges the battery. If the battery is low, that can add a lot of current at least for a few minutes. Stock alternators generally maxed out at low rpm which helped protect the wires a bit even when the battery was heavily discharged.
Current out depends on the what the demand is. What you could measure on a machine or with a Volt-Amp-testor on the car would be maximum potential output at a given rpm.

'64 should have an fusible link.
Fusible Links in Charging Systems with Ammeter

To make new terminal connections, you'll need Chrysler type connectors and an open barrel crimper.
Do a search here for that info.

Click to expand...

My mechanic put in a new alternator line with a fusible link when they replaced it. So that part should be good.

As far as I know, the circuit board behind the instrument cluster is intact. I do have a spare circuit board. AFAIK, the gauges are presently not correctly connected, judging from the diagrams in the service manual.

Thanks for your input!

Actually. That may be off to a bad start.
Alternator output generally should not have a fusible link in it.
The link should be close to the battery as explained on the webpage about fusible links.

Sometimes additional links were employed on more complicated systems, or when the power junctions were done in the engine compartment. Read the webspage it should be pretty clear.

DelCity has everything you need.

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