BYPASS the AMMETER? (1969 A12)

[72RoadrunnerGTX]

That is a 60amp alternator engine compartment wiring diagram. I think you are missing an important notation there. It clearly states that when a 60-amp alternator is used from the factory, the dash harness ammeter leads are not intended to be used, “Cut & Tape”. Not seeing a parallel charging path if it was assembled as indicated. Parallel circuits of any kind can be difficult to diagnose and manufactures normally avoid such circuit designs for that reason. Recalls are a different matter, fast and cheap. One dealer I worked for, at about that time, did a lot of work on state police fleet vehicles with factory upgraded alternators, never saw one of those that didn’t have the dash harness leads cut back and taped from the factory.

 

[Nacho-RT74]

Yes I know! Thats why I added the extra info later and also mentioned what you circled. Didn’t forget that. But Check the thread I posted the link about the 74 with all wires on car and nothing cut and taped

74 diagram shows All wires being hooked up ( no cut and tape ) I leave home and can’t post more diagrams at this moment.

 

[Nacho-RT74]

Anyway, is still an option to get both wires still attached

you can also remove the black wire from bulkhead down the dash, change the packard terminal for an eyelet one, run it to ammeter and in that way the splice will be feeded by two 12 wires spliced into the 8 gauge alternator wire at ammeter stud.

I made a diagram to that but wait I get back home.

there are many ways to cook the same pork!

 

[Nacho-RT74]

finally back at home... and here is the 74 diagram on the sections we care... both are shown connected.

( CE2 code is the bulkhead )

 

[Nacho-RT74]

and this would be my next option using just the path throught the firewall but still using the wire between bulkhead and splice to reinforce the main splice feed ( if you don't want to use the existant 12 gauge alt wire along with the added one )

quick disconect link is an option too, for versatility

 

[RM23M9A]

electric fans is allways a compromise. Maybe a 80 amps alt could be not enough ( normally rated or named as 78 amps alt actually ). But that will depend on many variables. Sure NEVER source it from battery!!! allways from alternator. But... single or dual fans ? will work just with key in RUN ? or will work even with engine off and turning of by itself like modern cars ? whats the temp range cicle you plan on keep the fan working ? Using a temp sensor switch to cicle it on/off or being manually activated ?

Stock Mopar alternators, on $60-80 rate from part shops... mid to late 80s Mopars, normally used on turbocharged models such as Shelby Charger and similars. You can search it on line on Rockauto to confirm it. You could try that one first and if still not enough, upgrade it for more, but those are on $200 rate.

Could be a LOT of Parasitic drain there, if batt is not keeping charge

 

[RM23M9A]

and this would be my next option using just the path throught the firewall but still using the wire between bulkhead and splice to reinforce the main splice feed ( if you don't want to use the existant 12 gauge alt wire along with the added one )

quick disconect link is an option too, for versatility

View attachment 979327

There is is!!!!
Thank YOU!

 

[72RoadrunnerGTX]

quick disconect link is an option too, for versatility

Looks more like another unnecessary potential point of failure to me.

 

[Nacho-RT74]

Having the stock wiring still in use everything is softened

 

[Nacho-RT74]

Could be a LOT of Parasitic drain there, if batt is not keeping charge

Hence the reason for the high output alternator

 

[Nacho-RT74]

There is is!!!!
Thank YOU!

yeap but this is the setup I have been using on my car for years. If the stock wiring is still in good conditions ( or In your case being new ) there is no reason to not keep it in use and just reinforce like this:

and this will be the one I'll be mostly sure running when reassembling my car

adding the quick disconect link and using just one red wire to keep just one fuse link. I completely trust having the good alt I have, the batt will barelly source the system, so no need to keep it double. And still the single one will be 10 gauge.

quick disconect link use barrel kind terminals which are way harder to beat than packard ones. They are used for trailers main wire.

 

[RM23M9A]

and this would be my next option using just the path throught the firewall but still using the wire between bulkhead and splice to reinforce the main splice feed ( if you don't want to use the existant 12 gauge alt wire along with the added one )

quick disconect link is an option too, for versatility

View attachment 979327

Yeah this looks like the ideal setup.
However, since all of my harnesss came in, and no longer waiting on part, I couldnt wait. Put it ALL together. Once Ammeter leads were hooked up, clock began to work, had dome light,flashers etc. Had to struggle with why all guage lights didnt light up. I found that the aftermarket black twist in bulbs apparently werent making contact. Also noticed I hadnt tightened the Ammeter leads! So back on my aching back on the damn floorboard I go. After replacing the NEW light sockets for the 2 remaining OEM ones I stil had? ALL of the guage lights work! 1st time in 30+ years. I beleive the fuel guage finally moved bit, but AMMETER WAS PEGGED at +40! I should tighten rhose nuts down! Hard to get at from underneath.
I replaced Voltage regulator, coil, ECU, secondary wires, Dimmer switch, circuit board, V limiter, distributor cap, ballast resistor, engine harness.....Uuugh. 2 ( NEVER BUY A DIMMER SWITCH FROM Classic Undustries" theyre JUNK), SO 3 accelerator pumps and the bitch fired right up. Have some tweeking to do, as now console lights are inop, (Probably that pink/yellow wire I found running down to kick panel. But IT runs! More fixes wiring issues sure to come. Hell RADIO even came on, minus 2 speakers... All in all, a good 03:00 a.m. project.
Now we'll see how it runs!

 

[Nacho-RT74]

Be sure batt is completely charged and try again.

a +40 ammeter reading indicates a fully discharged batt or accesories being sourced from batt post being sourced at the same time batt is also discharged

althought is pretty much normal having a full charge reading by couple of minutes, it should begin to go slowing down to 0.

on a normal operation system using the car as a driver, an ammeter will register a charge reading (+15/25 ) after crank up for 5 to 10 minutes going down along this time to recover what the batt lost on starter motor ( depending on alt capacity ). While more time got cranking the starter motor, will get more charge reading for more time.

and honestly, make the parallel path is easier than modify a brand new wiring system. Trust me it will work. Being working like that for 6 years on my AC car ( once again, being a driver ) and using a 6 relays setup for headlights and each one of the AC-Heater blower speeds... and sourced from the ammeter stud on black side

 

[Nacho-RT74]

i guess also you got +40 with carb choke fast iddle cam engaged!

You can also reduce the charge reading turning on headlights. This will reduce the load going through the ammeter ( not through the bulkhead though) but will take a bit more time to get it fully charged.

the ammeter stud nuts must be tight but don’t overtight because can get damaged the insulators or even the ammeter itself inside.

you can try to tighten them up with two wrenches, holding the nut on bottom to keep safe the insulators and studs from spinning.

 

[RM23M9A]

Yeah It went down to 0!
Or in the middle, battery DID sit a while and isnt the best brand, i need a "Tartop' with the red caps! But theyre freakin $300+..... Sucker fires right UP. Im actually amazed, with all the wiring I took out!
A little experience did help,. BUT there are these 2 brown wires that attatch to the wiper switch? Pain in the assss trying to hook those up with cluster in dash.

 

[Nacho-RT74]

wiper washer button I guess.

well, as long you have a 0 reading on ammeter as much as posible it means no load or minimal loads going through on any sense ( from batt or to batt ). No load it means no heat. No heat, safe ammeter setup. And all your fears of the subject of this thread are gone

 

[RM23M9A]

wiper washer button I guess.

well, as long you have a 0 reading on ammeter as much as posible it means no load or minimal loads going through on any sense ( from batt or to batt ). No load it means no heat. No heat, safe ammeter setup. And all your fears of the subject of this thread are gone

Yep, after warming up a bit, ammeter seems to set at just + of center. Guessing battery being 10 yrs old, not to mention how much Parasitic Drain's been on it. I also installed one of these replacement (RALLYE GUAGE circuit boards), new [Year One Dimmer switch] which works great! Ive learned that if the Ammeter leads are a bit loose at all, you have NO dash lights on the R side. Fuel guage not working, (It used to read 3/4 all the time), "Auto Meter" Oil & Temp guages are UNDER the dash. Wiper switch worked last night, NOT this morning..lol, I dread removing this damn cluster AGAIN.

Still has some tweeking to do, console lights etc. Took it for a drive just now. (97° outside), ran like a bat outta hell for a while, then started doing this "Partial cruise RPM to aceleration" hesitation. Also noticed a fuel leak/dripping from LRear frame area right behind Left Rear tire! Oh goodie! More work. It did this same thing before I gutted the wiring! Im too old for this crap with NO LIFT!
These CARTER fuel pumps ever been problem for anyone? Noticed it seems to leak OIL. Not to mention what apears to be a CRACK on the outlet side of the pump itself...
Uuuugghh!!

 

[RM23M9A]

 

[Should be playing golf]

Solve all your problems instantly by running a parallel 8ga. red wire directly from the Alt. battery post to the + battery post. Leave the factory wires through the bulkhead to the ammeter, etc. (This wiring will continue to power your headlights, ignition, fuse box, etc.) Just replace any damaged packard terminals or anything else that may have been messed up. Your ammeter will stay centered due to low current flow and no chance of any flames!! Simple and easy and no need to remove the front seat, etc. just to work under the dash. This is recommended by PowerMaster by the way.

 

[1968rt]

http://www.madelectrical.com/electricaltech/amp-gauges.shtml in case you dont have the diagram already