Ammeter Bypass a Must?

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QuickDart360

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Just have a question regarding ammeter bypass. I don't have a radio or high draw accessories that use alot of electricity. At one time my ammeter gauge petered out. The strip at the back burned and no more reading. No burned wires or bulkhead connectors, surprisingly!!! Also alternator is stock low amp. Question is is it absolutely needed to bypass or am I looking for trouble at not addressing this.
 
Just have a question regarding ammeter bypass. I don't have a radio or high draw accessories that use alot of electricity. At one time my ammeter gauge petered out. The strip at the back burned and no more reading. No burned wires or bulkhead connectors, surprisingly!!! Also alternator is stock low amp. Question is is it absolutely needed to bypass or am I looking for trouble at not addressing this.
It’s so painless in my opinion that there’s no real reason to not do it. Just another less potential problem to eliminate down the road.

Jake
 
There is no actual reason to do it. Some will post scary fire stories. And! While that is possible, so is winning lotto tonight.

It is super simple to do this job. So, if you wish to do so..... your biggest issue is what gauge to get and where to put it.

I wonder if they make one to replace the factory amp gauge.
 
I did the "fleet bypass" to eliminate high current from going through the bulkhead connector. The alternator wire feeds through a hole with a grommet beside the bulkhead connector.

I figured it was a good compromise to keep a working amp guage and reduce the possibility of high resistance in the bulkhead.
 
I forgot to mention my car is a 1975 dart sport. I don't know if this year is any different from other years as far as wire thickness to bulkhead and any other change based on year model alone? Hey 66 fyssh what is the fleet bypass? Now you have me intrigued!:rolleyes:
 
You can reach up under the dash without removing anything and move one wire so both are on the same post. Takes two minutes. If the gauge is fried anyway, why not just do it?
 
I forgot to mention my car is a 1975 dart sport. I don't know if this year is any different from other years as far as wire thickness to bulkhead and any other change based on year model alone? Hey 66 fyssh what is the fleet bypass? Now you have me intrigued!:rolleyes:


1. If you have had a problem with the amp gauge bypass it. It is only there for you to see what's going on.
2. it seem you know that even if you bypass the gauge by connecting the wires as has been suggested, you still are feeding through the bulkhead connector which is probably the bigger potential problem down the road.
3. I've got a box of spare junk yard pull gauges for backup for my fleet, but I believe new ones are actually being reproduced now and would suggest if they are any good.
 
I forgot to mention my car is a 1975 dart sport. I don't know if this year is any different from other years as far as wire thickness to bulkhead and any other change based on year model alone? Hey 66 fyssh what is the fleet bypass? Now you have me intrigued!:rolleyes:

You can find the "fleet wiring" in some of the manuals. This is a factory (or maybe dealer option) with the 60? or 65A optional alternator. "What they did" was to cut and tape one of the ammeter wires, then run a SEPARATE larger feed wire through a separate dedicated grommet in the firewall

Go to MyMopar and download some factory manuals..........free

MyMopar - Mopar Forums & Information - MyMopar Tools/Reference

One place you can find example wiring of this is the 72 Plymouth manual, in the wiring diagrams they call it "65 Amp alternator--Satellite" on page 8-167

New grommet and added wires at bottom of page

65amp.jpg
 
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You can reach up under the dash without removing anything and move one wire so both are on the same post. Takes two minutes. If the gauge is fried anyway, why not just do it?
The needle on my gauge was working intermittently now it's not I'm wondering if by doing or not doing a bypass had that possibly affect charging?
 
The needle on my gauge was working intermittently now it's not I'm wondering if by doing or not doing a bypass had that possibly affect charging?
Just "moving a wire" is not bypassing the ammeter in the context of these / related posts. More often than not, the problem is the bulkhead connector terminals.

If you have not done so, read the MAD article, even if you don't do it that way. That article explains the hows and the whys of this failure

Catalog

Also if you have a specific problem, it generally is way better to start your own thread rather than bring up old threads. It gets confusing with several problems mixed into one thread
 
Yess
Just "moving a wire" is not bypassing the ammeter in the context of these / related posts. More often than not, the problem is the bulkhead connector terminals.

If you have not done so, read the MAD article, even if you don't do it that way. That article explains the hows and the whys of this failure

Catalog

Also if you have a specific problem, it generally is way better to start your own thread rather than bring up old threads. It gets confusing with several problems mixed into one thread
Yessir! And Thank You! I know you've mentioned this to me personally before. And I apologize for any breach of protocol. On a lighter note I've been reading stuff you and other members have posted here as far back as 2008. All guys are an awesome wealth of knowledge and I appreciate everyone of you
 
To your question. Is it a must? No. If all your wiring is in good shape and ALL you need is a good ammeter, I would just replace THAT. On my 64, I inspected everything very closely when I got it because I was aware of that issue. But everything on this car looked great, so I cleaned everything up on the back of the cluster and it's been working fine since I brought it home in January of 2019......after it had sat in one spot since about 1980 or so. It's still working fine.
 
To your question. Is it a must? No. If all your wiring is in good shape and ALL you need is a good ammeter, I would just replace THAT. On my 64, I inspected everything very closely when I got it because I was aware of that issue. But everything on this car looked great, so I cleaned everything up on the back of the cluster and it's been working fine since I brought it home in January of 2019......after it had sat in one spot since about 1980 or so. It's still working fine.
The gauge hasn't moved in a bit. Then I broke the ear on my alternator. Bought a lifetime from auto zone. Didn't know it was shipped to China for a rebuild. Grrr. Had issues when a VR lead broke. Replaced that. Alt was putting out .01 more than batt voltage with field grounded. Replaced alt. New vr from China. So ordered a MP USA unit. Just was wondering, if the gauge being dead would affect things...and would just jumping it would alleviate any issues? And do I need to use another volt gauge? Where is a good source for a new factory one?
Thanks, Rusty... Sorry for Y'alls Massive Loss Brother
 
The gauge hasn't moved in a bit. Then I broke the ear on my alternator. Bought a lifetime from auto zone. Didn't know it was shipped to China for a rebuild. Grrr. Had issues when a VR lead broke. Replaced that. Alt was putting out .01 more than batt voltage with field grounded. Replaced alt. New vr from China. So ordered a MP USA unit. Just was wondering, if the gauge being dead would affect things...and would just jumping it would alleviate any issues? And do I need to use another volt gauge? Where is a good source for a new factory one?
Thanks, Rusty... Sorry for Y'alls Massive Loss Brother

Thanks for the condolences. It was a blow for sure.

Well yeah, If the amp gauge is DOA, I don't believe the alternator will charge, because the circuit will be broken. I think that's right.
 
Ammeters are simple and often can be fixed. The big problem with the actual ammeter is that the studs are not brazed/ soldered to the shunt. The studs pass through a stack of insulating washers and the dash housing, which is plastic for some models. So if the nuts get loose or the plastic softens, the studs get loose and lose good contact with the shunt. After that you have a "rolling snowball" except it's a "fireball."
 
Thanks for the condolences. It was a blow for sure.

Well yeah, If the amp gauge is DOA, I don't believe the alternator will charge, because the circuit will be broken. I think that's right.
Cool! I wasn't sure. I swore I read somewhere that the thing would continue to function but I don't see how that is that's main battery voltage coming in. Turn on my 74 Duster a lot of that stuff actually goes to the key switch after the fact, I believe. They had some mad scientist electrical engineers for sure. Back in the 90s I toasted my dash harness on my 68 Coronet 383 4 speed I just went out the junkyard and got one for 10 bucks it was a non-issue then. If I can remember it still kind of sucks doing it... and I was younger then lol
 
Ammeters are simple and often can be fixed. The big problem with the actual ammeter is that the studs are not brazed/ soldered to the shunt. The studs pass through a stack of insulating washers and the dash housing, which is plastic for some models. So if the nuts get loose or the plastic softens, the studs get loose and lose good contact with the shunt. After that you have a "rolling snowball" except it's a "fireball."
That's exactly what I got going on. I've hold it out a few times checked all the connections pretty much throughout the whole car but I'm having an issue with the nut itself on one side of that gauge not wanting to tighten down all the way as the stud is moving....
 
Ammeters are simple and often can be fixed. The big problem with the actual ammeter is that the studs are not brazed/ soldered to the shunt. The studs pass through a stack of insulating washers and the dash housing, which is plastic for some models. So if the nuts get loose or the plastic softens, the studs get loose and lose good contact with the shunt. After that you have a "rolling snowball" except it's a "fireball."

Yeah, that's why it's so important to inspect every now and again IF you're gonna use the original "stuff". Like on mine, it had some green corrosion "funk" all around both studs. It was working, but sporadic. Once I got everything operating room clean, it started working good again. I have removed the cluster a couple of times since just to "look" and make sure everything is still good. Only four screws, after all......versus a burnt down car.
 
Ammeters are simple and often can be fixed. The big problem with the actual ammeter is that the studs are not brazed/ soldered to the shunt. The studs pass through a stack of insulating washers and the dash housing, which is plastic for some models. So if the nuts get loose or the plastic softens, the studs get loose and lose good contact with the shunt. After that you have a "rolling snowball" except it's a "fireball."
74 duster. Definitely some plastic in there. Thank You. Any suggestions?
 
That's exactly what I got going on. I've hold it out a few times checked all the connections pretty much throughout the whole car but I'm having an issue with the nut itself on one side of that gauge not wanting to tighten down all the way as the stud is moving....

What car do you have?
 
Yeah, that's why it's so important to inspect every now and again IF you're gonna use the original "stuff". Like on mine, it had some green corrosion "funk" all around both studs. It was working, but sporadic. Once I got everything operating room clean, it started working good again. I have removed the cluster a couple of times since just to "look" and make sure everything is still good. Only four screws, after all......versus a burnt down car.
I must be missing something, as it appeared to me, that I can't get into the gauge unit to tighten the studs? On my 66 satellite I started every one of those pens for that round connector for the instrument cluster this applied to power and did the little fivev solid-state upgrade.. back when one Radio Shack in town at least old something even though the people that work there get go how to do anything but cell phones but I managed to find what I needed
 
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