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A weird electrical problem that shuts down everything.
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Author:  rebel_cat68 [ Sat Jul 03, 2010 1:10 pm ]
Post subject:  A weird electrical problem that shuts down everything.
Hey there all in the /6 community.
It's been a while since I had a problem of this magnitude.
I've had my -70 Duster since -96 and have never had this problem occur before.
I drove a total of 120 miles to go to a 3 day rock'a'billy festival. Had a short 5 minute stop at 40 miles at my friends house. No problems.
Then a 15 minute coffeebreak at 75 miles. No hint of any problems. Came to the hotel parkinglot and got the hotelkeys. Drove the Duster a 100 yards to a sidedoor and unloaded the car.
And THEN...NO POWER ANYWHERE. It was like somebody had stolen the carbattery during the last 10 minutes. Tried to jumpstart the car with cables in case of battery gone dead. Not so.
And the next day the power was back on and it started perfectly.
Checked the battery with a borrowed multimeter and it showed 13,2V.
So after the weekend was over I drove straight home (120 miles) with no stops this time. Purred like a cat with no signs of any problems.
Came home 5:30PM and unloaded the suitcases and nick-nacks. Took me maybe 10 minutes.
Checked if the problem reoccured...and yes there it was again...or wasn't, the electricity I mean. Completely dead AGAIN!
Tried with my own multimeter how much juice is between alternator and ground. Showed 0.02V! with the key in run.
Checked 10.30PM if the electricity had come back. NO.... but the next morning 6.30AM it was back again :roll:
Today I drove 5 miles and no problems whatsoever.

So the question is (after all my ramblings) --- What can cause this?!
Is it somekind of heatsoaking when the car stands still after a long drive?
But what electrical device can get a heatstroke in the enginebay and cut off everything electrical???
Hopefully somebody in /6-land can comment this.

Ooh, a PS. This Duster has had a heart-transplant by a former owner and it has a 360, but that shouln't be the culprit of this electricity gremlin.
Author:  60 Plymouth [ Sat Jul 03, 2010 1:36 pm ]
Post subject: 
Hey,

My car's electrics are not stock, but I had a similar problem, erratic on/off problems. In my wiring there's a fuse in an individual holder between the battery cable and pretty much everything else. I found that the fuse tended to loosen up in the holder and randomly cut. I just stuck a bit of copper I had in the trunk between one end of the fuse and its contact to tighten it up. Fising it properly would have cost me about £3 (I'm not made of money) for a new holder but it's held up ever since.

My wiring's not stock but you never know, might be worth a look.

Good luck!
Author:  Joshie225 [ Sat Jul 03, 2010 1:43 pm ]
Post subject: 
Sure sounds like you have a problem on the battery to ammeter feed. It's most likely the bulkhead connector or a bad fusible link. Could even be the small positive wire from the battery cable to the starter relay. The alternator feeds power to the other side of the ammeter and chassis loads through a separate set of contacts in the bulkhead connector. As a test you can connect a heavy gauge jumper between the + battery terminal and the + output of the alternator to see if the car will start and run.
Author:  wjajr [ Sat Jul 03, 2010 3:00 pm ]
Post subject: 
I second Mr. Skinner’s hypothesis. Same thing happened to my car the day I dragged it home on a trailer. I drove it on, we pulled it for four hours, and the only juice available was between the + & - battery terminals. The problem was in the bulkhead connector where the fusible link connects to feed the amp meter. A little giggle and the power came back on.

I would clean all the bulkhead connections while you are at it. Also check the tightness of the amp meter connections as well.
Author:  BUCKET 636 [ Sun Jul 04, 2010 1:13 pm ]
Post subject: 
I had no power anywhere the other day on slant. I checked all the fuses and relays, still nothing. Managed to jump start it off the starter motor and took it straight to the auto electrician. He tested things, turned out to be the negative battery cable that grounds on the engine block. The wires were only just hanging in the terminal, thus not getting a good enough ground for the circuit. Put a new cable on and vroom vroom. Drove it 400 kms on the weekend and no problems. You might have a bad earth connection somewhere? :?:
Author:  69a100 [ Sun Jul 04, 2010 3:36 pm ]
Post subject: 
Knock on wood here!!!!! I've had this problem also, no dome light, radio, lights, etc, etc, etc. It's a real PITA when it happens! My problem I haven't fixed yet, but I haven't had the problem in a while. When it has happened, I've had to jiggle the wires at the starter relay and that got me going, I have swapped relays and still have had it happen. The only thing I can think of in my situation is something in the wires in the starting curcuit at/to the relay. This is in a van so I don't have a bulkhead connector, all I know is I hate chasing electrical grimlins. Just another log in your troubleshooting. Good Luck finding it. When you find it, please report.
Author:  maxracer21 [ Sun Jul 04, 2010 4:03 pm ]
Post subject: 
Just a tip from an old man..........All older Mopars should be grounded in four places. They came form the factory like this and if they didn't, the dealer would complete the work.(usually)

1. Neg. battery to engine block

2. Neg. battery to radiator shroud

3. Engine block to firewall (braided wire)

4. Both engine heads to firewall (braided wire) not factory, but suggested.

This may seem a bit overdone but since I started doing this I have had very few electrical probs. You can leave out the heads if you have nothing grounded to them . Look closely you'd be surprised what's been done over the years, and absolutely do not ground the engine block by using a bolt on the head......Remember there is a head gasket there doesn't conduct that well unless it is copper. Hope this helps you guys
MaX
Author:  rebel_cat68 [ Mon Jul 05, 2010 10:06 am ]
Post subject: 
Drove today to work 10 miles and afterwards to the grocery and back home, 15 miles all in all, with no problems,
so I'm leaning towards the theory of heatsoaking after longer drive and then parking, with the enginebay hotter than usual.

The ground should be ok, since I a year ago put the biggest available cable going from battery negative to a new bolt on inner fender (and yes I scraped all paint off the fender first at the bolt).
Also almost the same size cable from engine block (not head) to the same bolt.
And as third medium size cable from right inner fender to the alternator bolt that you adjust belt tension.
....and a fourth small one from fender to light relay-box.

At the same time I tried to clean all the connections in the engine-bay with either sandpaper or file,including the 3 bulkhead connectors.
Also at the same time the fusebox' fuseholders below the instrument panel with dremel.
+ I put a small dab of battery terminal grease in every "abico" connector.


I was wondering if the only fusible link, that's connected to the middle bulkhead connector, can get heatsoaked from the exhaust and stop working ie. not connecting?
And then after cooling down start working again ie. connecting...can a fusible link act like this, at all?
If I take out the fusible link and put an ordinary fuse by the starter relay instead, what size fuse should it be?

Thanks for trying to help me out.
Sadly no annual Swedish "Power Big Meet" cruise for me this year. :?
Author:  wjajr [ Mon Jul 05, 2010 5:27 pm ]
Post subject: 
rebel_cat68:
Quote:
And then after cooling down start working again ie. connecting...can a fusible link act like this, at all?
I don’t think the fusible link is particularly sensitive to engine bay heat. However it could be the source of a poor connection due to a previous over current event, as it is the main feed to the dash, amp gage, and fuse panel. When that baby pops, everything goes dead.
Excessive heat from over current within the bulkhead connector can cause intermittent electrical problems.

Also I found when I replaced my bulkhead connector with a NOS unit, and refit it with new male & female brass connectors, one of connections did not get made tight because it was not fully seated in the connector cap. This caused an intermittent connection until corrected.
Author:  maxracer21 [ Mon Jul 05, 2010 7:18 pm ]
Post subject: 
I would suggest a jumper around the link for a test drive .........then you will know.........no harm in trying it
regards MaX
Author:  olafla [ Sun Jul 11, 2010 7:50 pm ]
Post subject: 
Hi rebel_cat68, I'm coming in with a comment a little late. I think Joshua Skinner is head on, and he pointed at a problem that many are unaware of, take a look at this link to madelectrical.com. I distinctly remember to have read about it on this forum too, but I haven't done a search yet.
I may mention that I worked with british motorcycles back in the "good" old days. They all had Lucas electrical systems, and the first thing my boss taught me, was "always check the ground wire before doing anything else, then the fuses, then you can start digging deeper!" Bikers riding british iron also used to name Lucas "the man who invented darkness"!
Olaf
Author:  Chuck [ Wed Jul 28, 2010 12:46 pm ]
Post subject: 
A voltmeter is your friend here. Turning on the headlights usually draws enough current to detect any problems.

Basically, ground the meter at the battery, then, with the lights on, start reading the voltage starting at the battery and working through the connections (battery to starter or starter relay, fusible link, bulkhead connector, amp gauge if the car has one, etc.). The voltage will drop (usually a volt or more) where the bad connection is. Make sure, when checking a connection, to read on the wire terminal and also on the stud if connection to something like a relay. A voltage drop there would usually be a tarnished or corroded connector.
Author:  Dart270 [ Wed Jul 28, 2010 1:02 pm ]
Post subject: 
I don't think anyone has mentioned this, but my vote is for...

Loose wires to the ammeter under the dash. :shock:

EVERYTHING except the starter main power is routed through this little gauge. I have had two cars do exactly what you describe - no lights, nothing, and intermittent. Fusible link would not cut off lights or other accessories.

Could be a bad gauge, but I bet it's just loose leads that need to be tightened. MAKE SURE to disconnect battery before crawling under the dash with a metal wrench.

This killed me for a few weeks on my beater '71 Dart back in 1989.

Lou
Author:  Chuck [ Wed Jul 28, 2010 5:11 pm ]
Post subject: 
Right Lou. I mentioned the Amp gauge above. When you check the nuts, it is best to REMOVE the TOP nut & wire(s), then tighten the REAR nut, then install the wires & top nut. Many times the top nut is tight but the rear nut is not, resulting in a bad connection & overheating of the wires.
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