'70 "Alternate" Ammeter wiring help anyone?

Wiring, lights, heater controls, anything electrical..
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PwrWgnWalt
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Joined: Wed Dec 31, 1969 6:00 pm
City: Butte
State: MT

Re: '70 "Alternate" Ammeter wiring help anyone?

Post by PwrWgnWalt »

Hi guys,

Upgrade has been GREAT! Ammeter is steady, but definitely shows deflection when load or charge is applied, as before.
Headlights are bright, heater blows strong, wipers move swiftly; everything works very well, even at idle.

pwadventurer, your drawing is exactly how I did it.
I need to get pics posted, but your drawing is spot on!

-Walt

User avatar
PwrWgnWalt
Sweptline.ORG Member
Sweptline.ORG Member
Posts: 388
Joined: Wed Dec 31, 1969 6:00 pm
City: Butte
State: MT

Re: '70 "Alternate" Ammeter wiring help anyone?

Post by PwrWgnWalt »

Here are the 4 Steps to doing this "Alternator Wiring Adaptation"... pretty simple, once I knew what to do. The scan of the Service Book page shows this all pretty well, it just didn't tell me what to do with the existing wiring at the Ammeter. (click pictures for full view)

1. Get heavy gauge wires to run the new lines. I used wires from a 1971 D200 Camper Special parts truck that had this done long ago; looks like either 8 or 6 ga. stranded wire. You use whatever fits your situation - at your own risk.

new BLACK wire- runs from the BATT post of the Alternator straight thru the firewall and to the Ammeter 'Charge' side, where the original black wires are (the original wires stay there, along with this new wire).

new RED wire - runs from the New Terminal Block on the inner fender (by the starter relay) straight thru the firewall to the Ammeter 'Discharge' side, where the original red wires are (the original wires stay there, along with this new wire).

Here's how that looks going thru the firewall...

Image

2. As for the New Terminal Block - I got one online somewhere (bought two, actually). The insulator cap is off for this picture - be sure to use one because if something touches this post and the chassis or body (ground), sparks WILL fly! :pale :shame
The New Fusible Link goes from the Starter Relay (large post) to the New Terminal Block.
The New Red Wire goes directly to the Ammeter from there (hard to see, but is at upper left of the Terminal Block, with yellow around the ring connector. Goes up by the firewall bulkhead connectors, held by the existing chassis wire clips, and then thru firewall, as pictured in Step #1)

Here's what the Starter Relay area looks like...

Image

3. As the Service Manual Picture shows, a Fusible Link replaces the original routing of the wires from the Alternator and from the Starter Relay at the Bulkhead connector block. Supposedly, if your fusible link is in good shape, you can just plug it into slot #16. My wiring was a disaster, so I made a new one (got a Fusible Link from NAPA).

Image

4. Here's where the Fusible Link in step 3 plugs in to... it bridges between (thus connecting) firewall bulkhead terminals #16 and #27. This is important to finish the circuitry and have everything work as intended (as good as - or better - than new!)

Image

I did it this way because I wanted to keep it simple and keep it stock. Wish I'd done this years ago!
Everything works very well - bright headlights, strong heater blower, wipers steady... no more accessory slowness or dim headlights when at a stoplight!

- Walt
:usa
1971 W200: green, built 360/NP435 4-spd, daily driver, 4.10 gears
1971 D100: "Dude" Super Banana Yellow, 318/727
1970 D100: Adventurer Sport, Red, 318/727, AC, pb, extra fuel tanks, and aluminum tailgate trim - all factory original.
1970 D200: light blue, 383/NP435 4-speed, 4.10 gears
1970 D200: Crewcab, brown, 318/727, pb, short Utiline box, Dana 60 (rear), 4.10 ratio gears
1969 W200: Crewcab, yellow, 440/435 4-speed, pb, short Utiline box, HD Dana 44 (front), Dana 60 (rear) 4.88 gears
1969 D100: Adventurer, brown, 383/727, pb, extra fuel tanks
1969 D100: Adventurer, medium blue, LA-318/727
1966 W200: Green, A-318/NP435 4-speed, NP201 Trxfr Case, 4.10 gears Powr Lok rear
1965 D200: Crewcab, turquoise, A-318/727 dash shift, Sweptline box
1964 W200: Green, A-318/NP435 4-speed, NP201 Trxfr Case, 4.10 gears Powr Lok rear

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