Quick amp question

[resq302]

Aaron,

Can you disconnect one fuse at a time and see what might be causing the draw on the battery when it is running?

[Pete in NH]

Hi Aaron,

Keep the negative battery cable disconnected until you find the problem or you will pull your new battery down too. As Brian has suggested pull out one fuse at a time to see if you can isolate the problem current draw down to one circuit. You can take out a fuse and then touch the negative battery cable to the negative battery post if you see a small spark as it touches, is still being drawn. Do you have a test meter with a DC Ampere position? If so place the negative meter lead on the battery post and the positive meter lead to the negative battery cable. If you get a meter reading current is being drawn. make all these tests with the engine NOT running and the key in the off position. From all the other lights and such that aren't working it sounds like your car may have a lot of the problems typical of 40 year old wiring. Try disconnecting and replugging in the bulkhead connectors several times to clean up the pins a bit. Also, when you do that look and see if any of the pins are melted, discolored or burnt.

[Captain D]

Hello Pete and Brian,

After everything electrical just died on me, I admit - I lost some patience and simply called AAA a few days ago to take it to a local garage where there is a Chrysler expert on hand to see if he could find something that I couldn't (actually, the fuse test and the test meter suggestions both are a good idea and I may still try it yet). The garage finally got back w/ me and said that everything, surprisingly, looks good with the new 60 amp alternator, new 60-65 amp electronic regulator, and new battery. They believe that the primary issue was with my old alternator, which was cranking out too many amps for a non-electronic regulator (in addition that couldn't handle that many amps from the alternator that was pushing a whopping 90 amps  ). Plus, my older battery was low, which was also why both the new alternator and regulator were working harder to charge that battery.

However,  the problem with the new battery was that it was/is new, but was produced last July. So with having a shelf life of a year of not being used, it was essentially dead when when I bought the dang thing. We charged it and everything seems to be okay, but the ammeter still reads close to the + 20 reading when we rev it up (however, the good news is that it seems to hover between the 0 and the +20 at idle). Tomorrow, I'm going to double check to see if the new regulator gets hot like it did a few days ago and maybe double check the amount of amps that the new alternator is producing (if possible), which "shouldn't" be over 60 amps. I suppose now I am a little weary that alternators seem to go above their designated mark seeing how my old one went much higher than indicated.

In your opinion, do you feel that I should return the new battery? They say at the shop that now that it is fully charged, its fine - but I definitely value others opinion. Also, I gave them a 60 amp maxi fuse to install, but said that it couldn't be installed because there was no way to install it due to space and they could not find a pig line connection...? If I can't get it installed, "it is what it is" I suppose, but is there any other way that you know of on how to get that installed, by chance?

In the meantime, I will definitely mention to them your suggestion regarding the fuse check. As far as the +20 alternator reading when revving the engine up, do you agree with them when they state that its just "the norm" more or less for my particular car when revving up the motor?

I'll be calling them again in the morning over at the garage and thank you for your time and input once again,
Aaron

[Pete in NH]

Hi Aaron,

I'm not sure I fully understand the explanation in your first paragraph. As best I can make out they were saying the alternator required more field current than the regulator could provide. Although I have to say when someone who is supposed to really know an area such as automotive electrical systems offers kind of a jumbled explanation, I have to wonder how well they know what they are doing.

On the new battery, the clock on the battery's life kind of starts when the acid is first poured in. So, if it sat on a shelf for a year unused and not periodically charged, that may be time you will not get back out of the battery. That's one reason why you want to buy batteries from somewhere where the stock turns over fairly quickly. It's also a good practice to put a newly purchased battery on a charger for a while before installing in a car to make sure it's fully charged. The fact that you are still seeing +20 amp charge currents when you rev. the engine tells me the battery is either still not fully charged or defective in some way. Or the possibility is still there something in the car is not wired right. This is based on your reporting the system voltage is normal at 13.8 to 14.4 volts.Again, I would place the battery on an external charger and see if the charge current tapers off as the battery becomes fully charged. I'll leave to you whether you return the battery for another.

On installing the Maxi-Fuse, on a 69 the fusible link goes right from the 1/4 inch terminal on the starter relay into the bulkhead connector pin so it can be a bit of a challenge. A good automotive electrical shop should be able to pop the pin out of the connector and replace the pin with the new Maxi-Fuse attached. Perhaps they just didn't want to mess with it. The connector pins are called Packard 56 pins and you may be able to get them at NAPA. If for some reason the original fusible link blew you would have to replace it this way as well.

I do not agree with them that a continuous +20 amp at engine speed is normal. The battery current should taper off to near zero at some point. Either the battery is not fully charged, defective as in a shorted cell or there is some other wiring issue with the car.

[MaximRecoil]

On installing the Maxi-Fuse, on a 69 the fusible link goes right from the 1/4 inch terminal on the starter relay into the bulkhead connector pin so it can be a bit of a challenge. A good automotive electrical shop should be able to pop the pin out of the connector and replace the pin with the new Maxi-Fuse attached. Perhaps they just didn't want to mess with it. The connector pins are called Packard 56 pins and you may be able to get them at NAPA. If for some reason the original fusible link blew you would have to replace it this way as well.

I need to put a fusible link in mine; some previous owner put a regular piece of wire in there, probably 16 or 18 gauge, and they didn't even do a good job connecting it to the Packard 56 terminal. I have a proper crimping tool for open barrel terminals like that, but what gauge fusible link does it need? Is it a 10 gauge wire that connects to it on the other side? If so, I need a 14 gauge fusible link, which fortunately I can get at the local parts store (impossible to find a 12 gauge or bigger fusible link locally).

Also, do you know if the plastic connector housings for the bulkhead connector are available? I know you can buy the whole thing (for way too much money I might add), but I just need one of the three that push on from the engine compartment side of the firewall, because the genius that stuck in that regular wire in place of the fusible link also broke out the plastic surrounding that cavity, presumably while trying to get the Packard 56 terminal out of there, so that particular terminal no longer locks in place, it is just held in there by the friction of being inserted in the female terminal (which isn't much, I've had to push it back in a few times).

[Pete in NH]

Hi,

The fusible link was a blue 16 gauge link. The wiring it was connected to went to the ammeter as a #12 red wire.

That's kind of the issue that happened with field repairs, like people putting pennies behind the old plug house fuses, fusible links got replaced with plain old wire. That's one of the reasons I like to suggest Maxi-Fuses, you can get them almost anywhere. Even my local hardware store has them in those hardware tray assortments under automotive fuses.

I don't know about the plastic shells for the bulkhead connectors. I'm  sure at one time they were likely supplied by AMP or someone in the connector business like them. Perhaps someone else knows of a source.

[MaximRecoil]

Okay, I can get a 16 gauge fusible link locally too. In my car the charging circuit that goes through the bulkhead connector (ammeter bypassed in my case) doesn't get much current anyway, because I have a shunt wire going directly from the alternator post to the post on the starter relay (8 gauge with 12 gauge fusible link).

Were there any other fusible links in a '69 Charger from the factory, or is that 16 gauge one the only one?

[Pete in NH]

Just that one #16 gauge link as far as I know.

[Captain D]

As for my car - I 'think' that we finally got things straightened out. The old alternator was cranking out a whopping 90 amps and the old regulator that we put on last year appears to have been way too weak for it (and being non-electronic). And, the battery (being almost 5 years old) didn't help since, after being tested, it too was failing. Today, I pulled the 'new' battery and returned it to National Tire and Battery. I asked if they could test it and the battery not only failed, but failed miserably as defective.

I swapped it with a new one that was just produced last month vs. one made last year, installed it in the car, and fired it up. The great news is that now everything is functioning 100% better with a new 60 amp alternator, electronic regulator made to handle up to 65 amps, Interstate battery, and am having a tune up done w/ plugs and wires before the car leaves the shop tomorrow. As a side note, when I tested the car today before I went into work, the ammeter was reading just slightly to the right of the '0' both at idle and when revving up the engine as it is supposed to...finally!

The only thing that I wish that they would have done was to install my 60 Maxi-Fuse. They said that they couldn't get the installation assembly needed (or, as stated earlier in the thread, 'too lazy to do it,' which may have been the case), but I'll ask around to ensure that I get that in there as soon as possible. It feels good to finally wrap this stuff up - two weeks was a long time to be wrangling over this stuff,  . I'll be bringing the car home tomorrow morning, so we'll see how things go while on the road. Without doubt, I can't thank everyone enough for their willingness to lend me valuable knowledge, tips, suggestions - this site is amazing. When stuff like this happens, its always a learning experience and I will be sure to remember what I've learned. I hope that everything works out good and I can let you know how things go when we bring it home tomorrow.

Highest regards,
Aaron

[Pete in NH]

Hi Aaron,

Good to hear you finally have things worked out and that it was indeed a bad battery. With all the electrical issues behind you I hope you can enjoy driving your car!

[MaximRecoil]

I need to put a fusible link in mine; some previous owner put a regular piece of wire in there, probably 16 or 18 gauge, and they didn't even do a good job connecting it to the Packard 56 terminal.

That's kind of the issue that happened with field repairs, like people putting pennies behind the old plug house fuses, fusible links got replaced with plain old wire.

I fixed it for now. The plain old wire that was in there was spliced to a short section of the original fusible link. I didn't have a new Packard 56 terminal onhand, so I decided to reuse the original one. The problem was that it was still factory crimped onto that short remaining section of fusible link. So I drilled the wire strands out of the crimped area with a 1/16" bit, inserted the new fusible link, and then recrimped it with an open barrel crimping tool. Here's the result:



The rear open barrel tabs that are intended to be crimped around the insulation weren't long enough to crimp around the thick insulation of this new (16 AWG) fusible link, but whatever. The copper wire in the main crimp isn't going anywhere.

[MaximRecoil]

Just that one #16 gauge link as far as I know.

Thanks.

Why isn't there a fusible link located at the battery's positive terminal? That would practically eliminate the chance of a short happening in a section of the alternator-to-battery charging circuit that is unprotected by the fusible link (i.e., the 8 gauge wire between the starter relay and the battery).

In the car audio world, people with powerful amplifiers run 1/0 gauge wire out to their amplifier, and the rule of thumb is to put the fuse as close to the battery as possible, simply because it reduces the chances of a short happening in the section of wire before the fuse (which isn't protected by the fuse, obviously).

So I'm thinking you would have a safer setup if you put a 12 gauge fusible link directly at the battery's positive terminal, and butt-spliced it into the factory 8 gauge wire that goes to the starter relay, like so:



In my case I also have a shunt wire (8 gauge) going from the alternator post to the starter relay, and it currently has a 12 gauge fusible link at the starter relay, but no fusible link would be needed on that wire if there was one at the battery.

What do you think?

[Pete in NH]

Hi,

Yes, what you are suggesting certainly would be a safer system. It would offer some protection if something really bad happened in the alternator itself. Although I have to say it would take quite a high current to melt that 12 gauge link. The original #16 gauge link was an attempt at some form of minimal protection. That was 40 years ago. I think as time when on, the thinking on electrical system changed quite a bit to building in much more protection.

And yes, as you suggested with the example of installing big audio amps, it's always best to place the fuse protection as close to the battery or power source as possible in case something shorts to ground in the wiring.

[Captain D]

Great thread -

Thank you again Pete for taking the time to help me out!   I had the car out on the road the other day to attend a local event and everything functioned 100% just as it should have. I enjoy working on it, but I agree, nothing beats the open road hands down!  

As a side note, which remanufactured alternators have you  (or anyone as well) have had the most success with so far? In my search, my general area tends to get primarily Bosch and Driveworks for a 69' Charger. Ultimately, I may look into new vs. remanufactured perhaps but do you feel that either the remanufactured Bosch and/or Driveworks brands are worthwhile, by chance?

Thank you again for your time and I hope all is well over on your end,
Aaron

[Pete in NH]

Hi Aaron,

Actually over the years I've seen a lot of issues with re-manufactured alternators and starters to the point that I repair my own if I have a good core to work with. My 71 Charger still has its original starter and alternator on it. The alternator is on its third set of bearings and the starter has had new brushes and a new drive installed. So, I really don't have a lot of experience with current rebuilt units. Back in the day many police and taxi cars were Mopars and you always took a chance that your rebuild starter or alternator came off a car that was on the road 24/7 and had 150K miles on it and then got a fast sloppy rebuild job. So, I came to the conclusion if you had a good low mileage core rebuild it yourself and avoid that problem!

I would stick with well known names and avoid the chain store places like Autozone, etc.

[resq302]

I agree.  I tend to rebuild my own stuff now since the problem I had with the reman'd alternator that I had from A1 Cardone that had the pos. stud loosen up and start sparking.  Moparjohn also had an issue with his starter that he got from Autozone and that fried a good section of his wiring behind the alternator before it burned up the fuseable link.  We were about 3 hrs away from home when that happened and he has power windows and sunroof too.  Wouldn't you know it, thats when it decided to start raining.  At least him and my dad were out trying to get new wiring so I could splice in the fix for him.  Luckily Wes and Geri carry a good amount of spare parts with them and loaned it to John till he could get one in the next day at the local Napa.

[mhinders]

Just that one #16 gauge link as far as I know.

Thanks.

Why isn't there a fusible link located at the battery's positive terminal? That would practically eliminate the chance of a short happening in a section of the alternator-to-battery charging circuit that is unprotected by the fusible link (i.e., the 8 gauge wire between the starter relay and the battery).

In the car audio world, people with powerful amplifiers run 1/0 gauge wire out to their amplifier, and the rule of thumb is to put the fuse as close to the battery as possible, simply because it reduces the chances of a short happening in the section of wire before the fuse (which isn't protected by the fuse, obviously).

So I'm thinking you would have a safer setup if you put a 12 gauge fusible link directly at the battery's positive terminal, and butt-spliced it into the factory 8 gauge wire that goes to the starter relay, like so:

In my case I also have a shunt wire (8 gauge) going from the alternator post to the starter relay, and it currently has a 12 gauge fusible link at the starter relay, but no fusible link would be needed on that wire if there was one at the battery.

What do you think?

I'm not entirely sure about this, but I think the reason for not having a fuse or fusible link in the charging circuit is that it will blow the rectifier diodes if the circuit suddenly goes open. Something similar to an ignition coil, when you break the current you get the huge voltage spike (to the spark plugs in that case).
Maybe someone can tell us the exact theory behind it.

[MaximRecoil]

I'm not entirely sure about this, but I think the reason for not having a fuse or fusible link in the charging circuit is that it will blow the rectifier diodes if the circuit suddenly goes open. Something similar to an ignition coil, when you break the current you get the huge voltage spike (to the spark plugs in that case).
Maybe someone can tell us the exact theory behind it.

It actually does have a fusible link in the battery charging circuit from the factory (a 16 gauge one from the bulkhead connector to the starter relay stud), but it is somewhat in the middle of the charging circuit, leaving a significant section of the circuit unprotected. For example, if that 8 gauge wire that goes from the starter relay to the positive battery terminal shorts out, there is no protection there at all, and it could start a fire. If you splice a fusible link between the battery and that 8 gauge wire, you would then have protection for that ~half of the charging circuit.

[Pete in NH]

Hi Martin,

What you are referring to is called a "load Dump". The field rotor in an alternator creates a magnetic field that induces a voltage into the stator windings. As you point out like an ignition coil if you suddenly remove the load from the alternator this magnetic energy has to go somewhere and can create a high voltage in the now open stator windings. This is one reason why in modern cars with all their on board electronics you never want to disconnect the battery with the car running. The resulting voltage spike can damage some very expensive on board computers. There are some protective components build into modern automotive electronics to attempt to protect against this, but you can't always count on it. Even on our old cars, disconnecting the battery with the engine running is a good way to pop your electronic ignition box if you have one.

I would think if you were in the process of melting a 12 gauge fusible link , you already have big problems. The alternator may already have shorted diodes that are the cause of the link melting or if not is sourcing a lot of current that will heat up the diodes and may melt them. The heat sinking on alternator diodes is relative small and depends on a lot of air moving by them. Huge current demands will likely push the diode cooling beyond its limits.

[mhinders]

Thanks for the explanation Pete. 
Good to hear I'm not always lost in the woods... 

[MaximRecoil]

I would think if you were in the process of melting a 12 gauge fusible link , you already have big problems.

Yes, like a car accident which results in some sheet metal pinching through that 8 gauge starter relay-to-battery charging wire. That's going to pull several hundred amps very quickly and will likely catch the insulation on fire before melting through the conductor. A car accident is bad enough, a fire makes it worse. Fusible links are only intended for worst case scenarios like that, simply to protect the wire so it doesn't catch on fire such as in the event of it getting clamped directly to ground somehow. It doesn't matter that it takes a lot of current to melt a 12 gauge fusible link, it only matters that it takes a lot less current to melt it than it does to melt the wire it is protecting, which is why the fusible link is always 4 gauges smaller than the wire it is protecting, and has special insulation designed to not catch on fire.