69 Valiant Charging Concern

[408STRKR]

69 Valiant with 70 style alt (tested and good) and new Mopar reg.
Brand new red top optima battery (old one fried after 4 years.
New engine harness, junction box and terminals male and female, electronic Hei msd ignition. 2600 cfm fan on toggle switch, amp running all 6 speakers, secondary fuse box for gauges, fan, line lol.
Ammeter when at idle sits at centre if not into decharge. When driving on highway ammeter goes into charge by 3/4 when flicking fan on, when I turn it off the ammeter goes to to 1/2 on the charge side. I’ve check the ground, harness has one field and other going to ignition. Does this mean the system is working properly?

Only on throttle the ammeter goes into charge but doesn’t pin to the end

 

[67Dart273]

You say "fan" what fan, heater, AC, engine cooling? You likely have it hooked to the incorrect side of the ammeter to get a proper reading.

What you need to do is (if temporary) monitor BATTERY voltage and see what that is doing

 

[408STRKR]

You say "fan" what fan, heater, AC, engine cooling? You likely have it hooked to the incorrect side of the ammeter to get a proper reading.

What you need to do is (if temporary) monitor BATTERY voltage and see what that is doing

Flexlite cooling fan on relay (high cfm), my secondary fuse box running all my accessories minus the amp is coming from a free (key switched) tab on the factory fuse panel. Does this mean I should power this prior to the battery side and where is a good location. My multimeter fried the other day so I can’t monitor to see what the battery is doing on or off throttle, that’s a good starting point. Will do this and check back. I mean the reg seams to be working, if I leave that cooling fan on for good period of time, it will drain the battery

 

[Mattax]

The ammeter, when properly wired, shows whether the battery is charging or discharging and how much.
The battery is nominally a 12 Volt power supply.
The alternator is nominally a 14 volt power supply.
The two power supplies are joined to the sub circuits at a welded splice, not the fuse box.

You'll have to fill in the rest, but adding additional electric loads requires knowing roughly what the loads are (watts or amps) to be sure they don't exceed the supply or ground wiring.

Ammeter: Pulsating Alternator Gauge

If you want to keep these accessories than consider a variation one one of the heavy duty or fleet wiring arrangements. You can then add an auxilery fuse box for the new circuits and relays (headlights is a useful one) to the terminal block on the other side (alternator side) of the ammeter.

like this one

 

[408STRKR]

The ammeter, when properly wired, shows whether the battery is charging or discharging and how much.
The battery is nominally a 12 Volt power supply.
The alternator is nominally a 14 volt power supply.
The two power supplies are joined to the sub circuits at a welded splice, not the fuse box.

You'll have to fill in the rest, but adding additional electric loads requires knowing roughly what the loads are (watts or amps) to be sure they don't exceed the supply or ground wiring.

Ammeter: Pulsating Alternator Gauge

If you want to keep these accessories than consider a variation one one of the heavy duty or fleet wiring arrangements. You can then add an auxilery fuse box for the new circuits and relays (headlights is a useful one) to the terminal block on the other side (alternator side) of the ammeter.

like this one
View attachment 1715961963

Great info, that’s likely what’s happening as the system is grabbing from battery side of things. When you say “headlight” terminal block, do you mean tap into junction box spade connector terminal, existing fuse box terminal, or just find the wire under dash and cut/ splice into?

Best,

Jay

 

[67Dart273]

The basics are the battery ONLY is on one side of the ammeter. The loads and alternator are on the other side. Some vehicles violate this rule, AKA later A bodies. The "path" for the battery is battery---starter relay big stud---fuse link--bulkhead connector (RED) and to ammeter. Through ammeter (BLACK) to in harness WELDED SPLICE. From there branches off back through bulkhead connector to alternator, and from the splice, feeds the ignition switch "in", feeds the fuse panel "hot" buss and feeds headlights switch (only, not park/ tail) and depending on model, some other things, wipers, maybe

This diagram is not correct for all years, but generally. This is from the MAD article concerning ammeter and bulkhead connector failures:

You can clearly see in this simplified diagram how the ammeter is separated. The main starter cable does not count

Catalog

 

[Mattax]

Great info, that’s likely what’s happening as the system is grabbing from battery side of things. When you say “headlight” terminal block, do you mean tap into junction box spade connector terminal, existing fuse box terminal, or just find the wire under dash and cut/ splice into?

Best,

Jay

The goal is to shorten the path to headlights themselves.

Power flows from the alternator to the main splice, then to the B1 terminal on the headlight switch, to the hi/low swith and finally to the headlamps. Diagram below shows the concept even though its '67 which has differnet wire colors and connector positions.

Notice how long that path is. Also that the wires to the headlamps are only 18 ga. and the wire to the dipswitch is only 16 ga. That was OK when new and using 40 Watt headlights.

A relay with connected to the alternator output terminal shortens the path and reduces the connections it goes through.
It also means the power to the headlamps aren't sharing the alternator output wire with whateever else is demanding power.

The relays don't have to be spliced into the original headlight feeds.

You can use a connector that plugs into the original socket for one of the headlamps.
Diagrams and kits are on Daniel Stern's website. (DIY, which might be best if you are building an auxilery fuse & relay box)
Rob Yule makes and sells a plug and play harness with relays. Search for threads about Crackedback relay harness. A lot of people like the plug and play along with the quality and support.

 

[408STRKR]

The ammeter, when properly wired, shows whether the battery is charging or discharging and how much.
The battery is nominally a 12 Volt power supply.
The alternator is nominally a 14 volt power supply.
The two power supplies are joined to the sub circuits at a welded splice, not the fuse box.

You'll have to fill in the rest, but adding additional electric loads requires knowing roughly what the loads are (watts or amps) to be sure they don't exceed the supply or ground wiring.

Ammeter: Pulsating Alternator Gauge

If you want to keep these accessories than consider a variation one one of the heavy duty or fleet wiring arrangements. You can then add an auxilery fuse box for the new circuits and relays (headlights is a useful one) to the terminal block on the other side (alternator side) of the ammeter.

like this one
View attachment 1715961963

My 69 Valiant does not have a terminal block in-line with Alt side, alt to junction box and to the ammeter. So where is a safe option to tie in to the alternator side prior to ammeter?

Jay

 

[67Dart273]

My 69 Valiant does not have a terminal block in-line with Alt side, alt to junction box and to the ammeter. So where is a safe option to tie in to the alternator side prior to ammeter?

Jay

You have, in a VERY roundabout way, stated the entire problem!!

I suggest you read the MAD article at the link I posted earlier. Even if you do not use the method they did, that article gives a very good overview as to what the problems are

Look again at the simplified diagram I posted. EVERY terminal point in that diagram is a potential problem area due to corrosion, undersized wire and terminals, larger added alternators, and large added loads

The "main" culprits are the bulkhead connector terminals and the ammeter and it's terminals.

There is no "safe" place unless the circuit is "right up to snuff" and in many cases UPgraded That is why so many of us have done some sort of bypass and eliminated the ammeter. This basically turns BOTH the black and the red ammeter wires into "infeeds" into the pass. compartment, and removes charging current from them, so that your REDUCE current going in/out of the passenger area, and provide a larger dedicated charging path to relieve the old wiring

Your only "safe" spot if there is one---is at the alternator output stud. AND THAT ONLY APPLIES if the alternator is the operational power source for the majority of time your heavy load is being used.