Power sometimes

-
MOPAR SAVAGE

MOPAR SAVAGE

Well-Known Member
Joined
Oct 18, 2018
Messages
52
Reaction score
30
Location
Canada
Good morning all
Looking for some trouble shooting help my car is a 1970 340 duster auto and I seam to have power sometimes dome light door buzzer even enuf to start then once the car is off I have nothing until the next day
I have replaced engine to batterie ground and am planning a optima batterie to help with the fans and fuel pump etc
I want to do the mad bypass but would like to have the car in running order before I start any help is greatly appreciated
Pic of my baby

20181031_165248.jpg
 
MOPAR SAVAGE said:
Good morning all
Looking for some trouble shooting help my car is a 1970 340 duster auto and I seam to have power sometimes dome light door buzzer even enuf to start then once the car is off I have nothing until the next day
I have replaced engine to batterie ground and am planning a optima batterie to help with the fans and fuel pump etc
I want to do the mad bypass but would like to have the car in running order before I start any help is greatly appreciated
Pic of my baby

View attachment 1715268411
Click to expand...

Probably the bulkhead connector, or loose (maybe even burning) amp meter terminals.
 
So in theory I could connect the 2 ammeter wires to check before doing the mad bypass
 
I'll give it a go and see what happens got heat in the garage yesterday so can finally go out and work in winter its - 28c here today so good shop day
 
Just want to put this out there. Check the plug from the starter switch in column that goes to the main harness.
I had the same problem with my 70 Duster. The plug connector wire was burnt causing resistance till it stopped starting all together.
 
MOPAR SAVAGE said:
So in theory I could connect the 2 ammeter wires to check before doing the mad bypass
Click to expand...

It's not a theory, but a fact.:D
Due to the heat caused by the amps flowing through those amp meter connections they can get loose and cause intermittent connections. (which makes the heat even worse)
Sometimes those factory amp meter connections are all charred and can even cause an actual fire.
 
What size rims/ tires/ offset are on the back of your duster? Planning on buying some cragar s/s in spring and that is exactly how I want them to fill the fenderwells
 
I would look at battery cable terminals, then fusible link and bulkhead terminals/connections before considering the amp gauge itself.
 
Steve 225 said:
What size rims/ tires/ offset are on the back of your duster? Planning on buying some cragar s/s in spring and that is exactly how I want them to fill the fenderwells
Click to expand...
They are 295/50/15 not sure of the offset I can measure when I have the rims off again
 
MOPAR SAVAGE said:
They are 295/50/15 not sure of the offset I can measure when I have the rims off again
Click to expand...

thank you, love the way it sits

are the rims 8"or 10" wide
Btw best of luck with getting it to start consistently
 
Steve 225 said:
thank you, love the way it sits

are the rims 8"or 10" wide
Btw best of luck with getting it to start consistently
Click to expand...
I'll have to check they were on the car when I go it but they way they bulge I'm guessing 8 inch lol
 
Not trying to be mean..........you need to learn some systematic troubleshooting, you need "some stuff." Some alligator clip leads, a 12V test lamp and a multimeter. AND wiring diagram(s) / factory service manuals

You can download service manuals and wiring diagrams free from MyMopar

The MAD article is a how - to on the ammeter/ bulkhead connector problem BUT IT also gives you a nice simplified diagram of primary power distribution in the car

Catalog

amp-ga18.jpg


Follow along the above diagram:

There are minor changes over the years, but the "big stud" on your starter relay is not only one of the relay contacts, that stud acts as a major junction point. From there, battery power goes through the FUSE LINK and through the BULKHEAD CONNECTOR to the AMMETER (RED). Through the AMMETER, out (BLACK) and to the WELDED SPLICE. This is a factory spice under the dash in the harness a few inches from the ammeter. That splice feeds off (depending on year/ model) to the headlight switch, ignition switch, and fuse panel "hot" buss

If you sometimes have "nothing" meaning no dome lights, no head lights/ parking lights, the trouble is likely in this area, the bulkhead connector, the ammeter terminals, or rarely, but does happen, the welded splice fails.
 
67Dart273 said:
Not trying to be mean..........you need to learn some systematic troubleshooting, you need "some stuff." Some alligator clip leads, a 12V test lamp and a multimeter. AND wiring diagram(s) / factory service manuals

You can download service manuals and wiring diagrams free from MyMopar

The MAD article is a how - to on the ammeter/ bulkhead connector problem BUT IT also gives you a nice simplified diagram of primary power distribution in the car

Catalog

View attachment 1715268572

Follow along the above diagram:

There are minor changes over the years, but the "big stud" on your starter relay is not only one of the relay contacts, that stud acts as a major junction point. From there, battery power goes through the FUSE LINK and through the BULKHEAD CONNECTOR to the AMMETER (RED). Through the AMMETER, out (BLACK) and to the WELDED SPLICE. This is a factory spice under the dash in the harness a few inches from the ammeter. That splice feeds off (depending on year/ model) to the headlight switch, ignition switch, and fuse panel "hot" buss

If you sometimes have "nothing" meaning no dome lights, no head lights/ parking lights, the trouble is likely in this area, the bulkhead connector, the ammeter terminals, or rarely, but does happen, the welded splice fails.[/QUOTE
Oh absolutely I do need to learn some trouble shooting just thought I would
Click to expand...
Oh for sure I need to learn trouble shooting I wanted to see some suggestions on where might be the best place to start I do have all the tools to get started and the wiring diagram but no service manuals
 
Found the first but of trouble in the car last night
So what causes the fusible link to go in this circuit over charge from the altonator coming back ,bad ammeter, old age lol

20181230_204303.jpg


20181230_204630.jpg
 
MOPAR SAVAGE said:
Found the first but of trouble in the car last night
So what causes the fusible link to go in this circuit over charge from the altonator coming back ,bad ammeter, old age lol

View attachment 1715268892

View attachment 1715268893
Click to expand...

Looks like a bad repair has been done there before.
But hey, at least you found a good reason for your power loss, because that wire supplies all power for the cabin.:D

I pulled that link and replaced it with a breaker, because the last thing I want is something burning under the hood.
 
Age is the main culprit. All of these components were minimally adequate for OEM loads when new. As the wiper pivots wear and bind, heater core gets partially clogged, those motor loads increase. At the same time copper terminals corrode to become the weakest link in the current path. What you're looking at is typical points of failure. That's factory disconnect shown in your hand... I've seen it melted to the point that I had to whittle away plastic to separate it. All of it was garbage.
The worst thing we can do is add a bunch of aftermarket loads on what was barely adequate when new. When we add high amperage stuff like radiator fans, stereo amps, different headlight bulbs, etc..., we should use relays and get the high current directly from the source. common method is adding ring terminals at the starter relay stud.
Looks like there might have been some cutting and splicing in going on there too. Is that tan wire a factory splice?
The madelectrical bypass does do away with some of these weak terminals but also deletes the amp gauge assuming it would be the next point of failure in the path. That can be a cure all for the basic all stock example but how add on accessories are wired is still a factor.
 
Last edited:
TrailBeast said:
Looks like a bad repair has been done there before.
But hey, at least you found a good reason for your power loss, because that wire supplies all power for the cabin.:D

I pulled that link and replaced it with a breaker, because the last thing I want is something burning under the hood.
Click to expand...
What amp breaker did u use when u replaced it
 
RedFish said:
Age is the main culprit. All of these components were minimally adequate for OEM loads when new. As the wiper pivots wear and bind, heater core gets partially clogged, those motor loads increase. At the same time copper terminals corrode to become the weakest link in the current path. What you're looking at is typical points of failure. The worst thing we can do is add a bunch of aftermarket loads on what was barely adequate when new. When we add high amperage stuff like radiator fans, stereo amps, different headlight bulbs, etc..., we should use relays and get the high current directly from the source. common method is adding ring terminals at the starter relay stud.
Looks like there might have been some cutting and splicing in going on there too. Is that tan wire a factory splice?
The madelectrical bypass does do away with some of these weak terminals but also deletes the amp gauge assuming it would be the next point of failure in the path. That can be a cure all for the basic all stock example but how add on accessories are wired is still a factor.
Click to expand...
Very true the previous owner added a lot of electrical equipment fan fuel pump electric cutouts for the headers tranny cooler fan
I plan on putting in a fused block and having a relay give it power straight from the batterie once I sort out the problems I'm having now
As for the tan wire I do believe it is a factory wire
 
MOPAR SAVAGE said:
What amp breaker did u use when u replaced it
Click to expand...

Contrary to some opinions on here I used a 30 amp self resetting breaker and have not had a single issue with it since. (5 years now)
The general opinion is that the breaker or fuse should be capable of carrying the amps that the car could ever need on that circuit.
I know for fact that my car doesn't need 30 amps going into the cabin even with every accessory running at the same time including my stereo.
 
I wouldn't do just some things now, like madelectrical bypass, that might move the fire to inside, under the dash. I suppose you could simply patch repair whats there for the meantime. Best plan is dive in and correct it all at once.
 
MOPAR SAVAGE said:
Very true the previous owner added a lot of electrical equipment fan fuel pump electric cutouts for the headers tranny cooler fan
I plan on putting in a fused block and having a relay give it power straight from the batterie once I sort out the problems I'm having now
As for the tan wire I do believe it is a factory wire
Click to expand...

To add to what was just said,
The breaker I run is only for the cabin power, and pretty much everything else is run via relays (fans, electric pump, and such)
This way the cabin power and wiring is only used to activate the respective relays instead of entirely powering whatever device.
This cuts down on the drain off the cabin available power.
(Like the headlight relays do for the light switch and hi/low button.)
 
RedFish said:
Age is the main culprit. All of these components were minimally adequate for OEM loads when new.
Click to expand...

I used to do HVAC service. Around here are a number of heat pump systems using an electric furnace as an air handler/ emergency (auxiliary) heat. Most all use the same 1/4" flag/ spade push on terminals as the bulkhead connector. An electric element is nominally 20A draw AND THOSE TERMINALS DO FAIL with only 20A through them.

furnace6.jpg


There's about 40 of the damn things in the photo below:

furnace4.jpg
 
Before and after schematics of a bypass setup. Also unpinning one at a time, cleaning and repinning all the connectors in the bulkhead helps as well as coating them with a dielectric grease afterwards prior to plugging everything back together to keep the corrosion down. However on mine i upgraded to a 50A alternator, so i upgraded its output wire going to the battery with an 8ga wire, and fashioned up a 12ga fusable link. The push in bulkhead terminals are packard 56 terminals and come in sizes for multiple wire gages. Fusable links typically should be made approx 5-6" long. a trip resettable breaker is a great alternate idea as well. Pico wiring products online sells fusable link wire in bulk, as well as packard 56 terminals and other electrical parts.

I may have an unburnt replacement connector. If interested PM me.

amp-ga18.jpg


Screenshot_20180801-081728.jpg
 
Last edited:
moparmat2000 said:
Before and after schematics of a bypass setup. Also unpinning one at a time, cleaning and repinning all the connectors in the bulkhead helps as well as coating them with a dielectric grease afterwards prior to plugging everything back together to keep the corrosion down. However on mine i upgraded to a 50A alternator, so i upgraded its output wire going to the battery with an 8ga wire, and fashioned up a 12ga fusable link. The push in bulkhead terminals are packard 56 terminals and come in sizes for multiple wire gages. Fusable links typically should be made approx 5-6" long. a trip resettable breaker is a great alternate idea as well. Pico wiring products online sells fusable link wire in bulk, as well as packard 56 terminals and other electrical parts.

I may have an unburnt replacement connector. If interested PM me.

View attachment 1715269457

View attachment 1715269458
Click to expand...

20190101_154443.jpg
 
You must log in or register to reply here.
-

Back
Top