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Why bypassing the ammeter is a GOOD idea!

I have my amp gauge disconnected on my 63 Ply after install new engine harness. the BH has heat damage and could have been pronounced after install of electronic ignition and compatible alt some years before. Not sure. I still have dimming HL at idle. In any case looks like BH had overheating problems for a looong time. I see options posted of re-routing wiring to obtain a safer-functional amp gauge or going to volt setup. What's the popular vote on this? And if any lay-person sketches are to be had for wiring great to see them.
 
I have my amp gauge disconnected on my 63 Ply after install new engine harness. the BH has heat damage and could have been pronounced after install of electronic ignition and compatible alt some years before. Not sure. I still have dimming HL at idle. In any case looks like BH had overheating problems for a looong time. I see options posted of re-routing wiring to obtain a safer-functional amp gauge or going to volt setup. What's the popular vote on this? And if any lay-person sketches are to be had for wiring great to see them.

Ron, basically if you want to use your ammeter, guys have simply routed a new wire (at least 8awg) straight through the firewall from the alternator to the ammeter and return with the wire from the ammeter to the starter relay post. All connections need to be clean and tight, with the isolators on the ammeter posts in good condition. This removes the problematic connection points and overheating of the BH. Fusing or a fusible link would help to protect against overcurrent conditions, which may lead to melting, short circuiting and fire under the dash, etc.

I don't think the ammeter itself is the issue for most of us, but rather the connections through the BH and ammeter posts. I am not a fan of these ammeters as stated however, just personal preferance. Anytime the cluster is removed or even reaching up under the dash behind the cluster, there's a risk of accidentally loosening the ammeter connections, leading to the noted problems. Bypassing the ammeter does not resolve the BH issues though.

The BH issues are generally caused by inadequately sized blade connectors and/or corrosion, too much current from headlights on for extended periods or possible short circuits and even batteries in poor condition that require constant charging can cause constant high current through this circuit. Too much current or points of high resistance such as loose or corroded connections results in excess heat.
 
Thank you for taking time to explain things.

There is an English metaphor.
I do not know how it would translate into another currency.
"Penny wise and Pound foolish".

Google helps!

Someone who is penny wise, pound foolish can be very careful or mean with small amounts of money, yet wasteful and extravagant with large sums.
 
@Ron H and @Glenwood

The BH is allways a weak point, but if you don't upgrade the alt will still get weak ponts all around, ie the ammeter. The deal is not just save the BH weak spot, but save the ammeter from get loads going throught if really is not needed.

Think on this, a Batt should be used just to crank the engine, after that, the alt should be the main power source never getting assisted by the batt by default, but just ocassionally.

After the alt upgrade EVEN THE STOCK BH terminals, without any bypass WILL BE safer! Trust on that.

The packard terminals are able to handle up to 30/35 amps safelly! And an average car like our cars usually works with that load ( or less ) on regular use at nights.

When you have a charge reading giving gas to the engine it means the alt is not just sourcing the car load but also the batt load to be charged back. That it means you can get maybe up to 50 amps going through the BH black wire terminal even just a 15-20 charge reading on ammeter. There is when the BH begins to be weak And thats why you will notice how ALWAYS the black wire spot looks worse than the red one. So, if you reduce/eliminate the batt recharge load, EVEN THE STOCK WIRING SETUP without any upgrade will be more comfortable. What do you need to this? A good alt what will never need to be assisted from the batt to feed the car loads
 
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And what are the votes?

Well, depending. Maybe on this thread will get one option winner, but on another thread will get another winner LOL. Is like get the elections in California or Texas ( just saying LOL )
 
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Greatly appreciate the advice and thanks Patrick 66 for allowing me to jump in your post for my benefit! I hope you obtained the info you were looking for. The tips presented some really deep thinking about this and also read the linked articles posted. I'm leaning to the amp bypass gauge hook up posted by glenwood with his explanation and of natcho rt74's comments and others as well. The latter gets me wondering what the vital functionality is, whether with amp or volt and then which is better to know in terms of "need to know" vs "nice to know". I got used the amp gauge over the 20+ years I've had my '63 and came in handy over the years encountering excess charging and/or knowing OK needle is where it's supposed to be should be all good w/ charging system. The volt meter does the same thing just on the volt chart. So if I follow: Run 8g wire (with fuse) from the alt to the c side of the amp then run a wire from the d side to the starter relay? I'll look at the new harness again to see what wiring is there to maybe use as I have unconnected leads thinking for amp gauge connection as it is.
 
the voltimeter is just a kinda a proportional reading of the charging status not a direct reading. Charge is about amperes not volts. what produces heat is Amp not volts. You can get 12 volts through a hair, but a hair won't hold the load any device requires, hence the fuse link is a 2 gauges smaller hypalion wire than the main wire. You can get 600 volts if you want there, but will blown at the amperes overload, not with volts, Hence I like better the amperes reading.

For the same reason the Voltage is a proportional relation with the load under same resistance, we control the amperage output from alt controling the Voltage input to the fields with a voltage regulator. We can't control what the car demands to work, but we can control the voltage.

Both gauges got his pros and cons, so there is not a perfect gauge for this. HOWEVER I can see where I have poor or high voltage reading just watching at the bulbs response, without really need a voltimeter. On the other side You can't know about the amperes status just watching a bulb. Volts are given by the power source, amps instead are sucked by the devices no matter how many volts it gets. Of course less volts will require more amps to work the sam.

try to image this.

2 guys pushing a car on a street, then arrive home and had to push it into a sloped driveway. They need more force to push it in, or one guy more to help them out without use more force.

Guys are voltage, force is amperes... The car will suck same force no matter how do you suply it!

what does mean this ? you can't control what the car will require to be pushed in into the driveway but you can controll the guys pushing it! ( here why we control the alt amperage output via voltage regulation )

You don't have neighbours around to help you out on push the car, so, need to supply the force the car needs with the same two guys... your two guys are the 12 volts batt ( around 13.5 if engine is running ) and you can't find more voltage anywhere in the car so you need to feed the amperage, no matter what. Hence the importance of get the right load supply all around the car, hence a good alt ( which of course are not the underrated factory alts used back in the days up to lates 70s )

Now this

if the guys pushing the car are hungry or thirsty, won't have the force to push the car... lets say you have how to feed them but the straw to drink a Gatored bottle is small... will take more effort to drink. Will get tired just sucking in the Gatored preciselly at that moment LOL ( heat ).... so you need good paths fo feed them!

so then...we have two stages here, The provisions and the paths... good paths won't make anything if you don't have the provisions but you need FIRST to get the provisions, THEN good paths. Here is where I tell you, even it seems you are fixing lot of problem bypassing the ammeter or bulhkead ( paths ), still will need the provisions to get the load satisfied. The baby will cry for the milk even on a big boob and nipple if doesn't have milk!!!


after this explanation, MY PREFERENCE aside also I like to keep all my stock system working like factory did and being still posible to make it safe, is to know when my car is not being feeded by the alt when the batt enters into the game with a discharge reading. The ammeter gauge gets a wider reading than a voltimeter and you will notice faster when something is going wrong with the ammeter than with a voltimeter.

everything about alt and wiring upgrade on stock system has being posted on couple of links I posted on my initial replies
 
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aaand... I don't think really an 8 gauge wire is REALLY a need. You can use 10 gauge and will be good. SPECIALLY if you keep running the existant wires at bulkhead. IF they are still on good working conditions they can still be there and run the new ones as a parallel paths. That will allow to use a smaller gauge parallel path, even a parallel 12 to the existant 12. But generally speaking IMHO 10 gauge is plenty for our cars still using AC ( actually heater blower sucks the same and compressor doesn't sucks a significant load, just the rpms goes down affecting the alt output ). Nothing wrong using 8 gauge, but honestly 10 is enough

on my link I put two fuse links, the existant original and the one on the parallel... I think posted a correction on that ( not a new diagram though )... it must be JUST ONE fuse link. 14 gauge is good for that and not bigger than 14. If you keep stock and parallel paths, will need to be spliced in just that fuse link.

you can also keep the stock alt wire and parallel, and just use ONE wire ( the thicker one bypassing the BH ) between amm and starter relay to make this job easier. Remember as I told on a previous post, Most of the load is/must really driven from alt side and not from batt side with a good alt. The batt BARELLY will get loads coming from ammeter side with an upgraded alt, so the wiring on that side will be less stressed too
 
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Interesting read, and ideas. My lowly two cents worth.
I am not any sort of electrician! Don't want to be. But, as some of you have read, lucked out in ways, have two sons who are. (They attempt to keep my act straight. Hard!)

As they have pounded into me, for electricity, there are rules. What works, what doesn't. Just like the parallel wiring I added on my 64, per Nacho's ideas. For parallel wires, the 'rule' is use the same gauge wire for both, or one larger gauge will take more load (amps), than the smaller. Second is, both should be about the same length. For mine, the two 12 gauge parallel wires are fine, even with a load like using headlights. The deflection at the ammeter is very slight, lasts only a moment, and settles down.

Ammeter itself...stock. Yeah, for it's age, still in good shape. The way I see it, ammeter, or voltmeter, is only as good as the connections. The studs on mine are good. Like anything else, they can be mis-treated.
Insulators on both sides of the mounting plate (panel housing), to keep those studs clear of any contact. One thing I didn't like is, even with insulators on both sides, there's nothing to keep the studs from grounding, 'between' the insulators, if things get tightened too much. But, my insulators somewhat seated into there, over time.
Other thing is, once mounted, no locking device for the nuts. I dropped a thin washer, and star washer on mine, before the nuts. Same thing after the leads were in place. Just to make sure, once tightened, they'd stay tight.
 
OK, please pardon my ignorance with this fantastic discussion so I don't miss-understand something and as well makes sense in my head: To create a new-safer method to wire the amp gauge, the BH is entirely taken out of the picture for wiring and thus no longer the heat/fire threat at the BH. What's obtained is a functional amp gauge by a connection from the ALT to the gauge w/ a fused wire; then the 2nd wire from the gauge to some connection on the starter relay? Using 8 or 10g wiring suggested sounds fine; BUT in this mix I should see what wiring is already there to trace down (meaning the new engine harness shop installed doing motor rebuild). I have a blue wire coming off the alt that terminates near the relay but was never connected assuming this is the same wire. Also there's a blue/green wire adjacent also not connected (wires are taped to the hills so assured tracing will involve more opening up of the mega-taped harness to determine). They are female blade connectors and there's no spots for them on the relay as it is.
 
Ok, the first step is a powerfull alt able to feed around 45 amps iddling as minimun as my opinion... no matter what you get on wiring or gauge! More is better, but AT LEAST a 45 amps iddiling alt

The fuse link is not really neded on alt side but on batt side. Why? On a short, the batt side is the only source able to keep feeding the fire. If you didn't have a batt running and just the alt, when you get a short, the engine will stall, because the short will suck put ALL the juice and alt won't be able to source it, so engine will die. Aside that, if engine is not running and get a short, the fuse link on alt side is out of the game, since is AFTER the main splice. The batt will keep sourcing the main splice.

So on the basics... yes, is just about a straight wire ( 8 or 10 gauge ) between alt and ammeter, then from ammeter to the starter relay/batt, with the fuse link on this leg.

THIS IS A SUGGESTION IDEA:
I would use a quick disconect link to be able to unplug these new paths just like you are able to discinect the bulkhead... just about versatility prefference. These are available up to 48" which allow to use a large section straight to the amm studs keeping the plug on engine side, and a short harness section with the other plug to splice there the wires up to alt and starter relay.
51EqGP7xRcL.jpg


Be sure ammeter is in good conditions, tight studs to the internal shunt, same as BOTH isolators there and good.

NOW, if STOCK wires are still in working order, you don't need to remove them, not at least the alt one. Just mantenience. They will be safer now with the new alt and batt added paths.

If decide to keep both stock existant ones, need to take in mind need JUST one fuse link on red lines... splice both in the fuse link ( 14 gauge ) or simply remove just the stock red one for simplicity
 
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About the wires you describe ( blue, blue/green ) have no idea what are the ones you could be talking even less if added for somebody.

Originally if stock mech regulator, you should be getting a blue wire and green wire up to regulator at firewall. Blue comes from ign switch, green runs up to alt field. This is the system what makes to work the charging system. If they are not present you won't have charge. Maybe are these the ones you mean? If so, you don't need to make anything with them, just conect them. You can get a newer reg system which are same old case look with elect internals. I have read goods and bad opinions about them thought.

However I can't talk really about the wires you talk without see them.
 
Looking at the theory behind the ammeter, it makes sense to eliminate it. The cars were not expected to be still used 50 years later, right?
When new, all connections were clean, wires had no corrosion and everything worked great. Add a few decades of heat, cold, dust, humidity and general wear and even the most trusty designs can fail.
Having charging current run through the firewall by way of a thin spade connection just seems risky doesn't it?
I bypassed the ammeter in my Charger when I added the Dakota Digital gauge cluster. I did it in my 75 Power Wagon last year. I still intend to do this to my other cars as well.
Hey, how do you like the Dakota digital dash? I'd like to get one for my Coronet.
 
The Dakota setup is great. The gauges are easy to read and they are always lit up when the car is running.
 
99.9 percent of us, with me being part of the .1 percent can't tell the difference between the information displayed on an Ammeter vs Voltmeter, why have it. It adds a un-necessary level of complication to the wiring of our cars with little or no benefit.. I want to set my car up to set-it and Forget it, why add something that will only add concern and not comfort?
 
Well Derwud, maybe it's something I've been accustomed to for so many years and recall a couple occasions where I found charging problems...loose connections, shorts, etc. seeing the gauge going unusually off in one direction or another. Sort of peace of mind when seeing the gauge where it's supposed to be. I never knew what an unsafe setup Chrysler had though and my BH is proof of that. So as I've been learning here there are methods to arrange it safely and bring the dead amp gauge in my dash back to life.
 
Nacho-rt74. Was going to send you a PM with these photos attached to chat a little more about...including Glenwood and Miller if they don't mind. Your box though is full; if you prefer can stay on this post or I can create a new one given it's length.

Ply motor.jpg Firewall Wiring.jpg
 
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