If you aren't a spammer, I apologize.
But who doesn't know what year car they are working on?
Ammeter bypass
- Thread starter bronze turbine
- Start date
But who doesn't know what year car they are working on?
When you add a direct connection from the alternator to the starter, you give a second path for current to flow between the battery and the alternator. The first path is from the battery to the ammeter to the alternator. This first path has a fusable link in the path. It will burn up if there is too much current in the path. The fusable link is a short piece of wire in the engine compartment near the bulkhead connector.
When you add a second path directly between the battery and the alternator, you reduce some of the current flowing in the first path, and if there is a fault somewhere in the first path it is less likely to blow the fusable link. Also, if you do not install a fuse or similar fuse link in the second path, then you can have a fire on that line if the alternator fails (ie diodes go bad).
OK, good point. Now you are starting to give more info that sounds like you are actually working on a car, so again, I'll apologize.
To answer your question, if you are working on a 60/61 Chrysler, almost all of this thread doesn't apply to you. Those cars use generators and not alternators. Wired different etc. I think you are getting some sort of back feed into the electrical system.
Chances are your friend's car burnt because of bad or loose wiring at the dash. The ammeters in the earlier cars are pretty robust.
72RoadRunnerGTX
New Member
1960 was the model year Chrysler changed away from generators to this alternator/ammeter across all platforms. Other than ’70 and up changes noted, the core charging/load distribution changed little since 1960 for this discussion. Some early models didn’t use Packard connectors at firewall passthrough, had a screw terminal bus connection. Agree, poorly maintained or abused connections likely the cause. As for the stuck full scale ammeter, disconnect the battery, if the ammeter does not center, it’s a mechanical issue within the ammeter, could be the result of heat damage at the ammeter terminals resulting from years of high resistance or loose terminals.
Sorry I did forget a major part of the info,on the car I worked on,the previous owner removed the generator and installed an alternator.
This car has the same setup as all the rest I thought.every picture I seen and info I read seemed like it was the same...
This car has the same setup as all the rest I thought.every picture I seen and info I read seemed like it was the same...
72RoadRunnerGTX
New Member
IMHO, Yes, to both questions, defiantly
They introduced them in 1960, but not across all platforms. The Chryslers still used a generator, although I have found some references to alternators being installed in some, possibly dealer installs. The 300 club has some discussion about it and the conclusion was that the 4 speed 300F had an alternator, but the automatics didn't. They also figured some, not all Imperials did too. Check the '60 FSM and they don't show an alternator.
I'm not sure about 1961 though.
Was the regulator changed too?
I'd say the first thing to make sure it is wired properly. Hard to tell without seeing it in person, but that doesn't sound right.
Thanks for posting. Years ago a vendor at Carlisle had a NOS Mopar C body bypass kit, I should have bought it (cheap money) for the part number alone.
Over the shorter-trerm I've been in this forum, there have been many things I never knew about or had heard of mentioned in here. The ammeter bypass is one of them. Never had heard of such instrument panel fires on C-body Chrysler products before. I had heard of the alleged ballast resistor issues, but never had experienced that since we got our '66 Newport in the fall of 1967, or my '70 Monaco, my '67 Newport in 1981, yet some gave me the impression it was a very common situation for a ballas resistor to fail and the car not start.
NOW, something DID change with the 1972 model year. When we got our new '72 Newport Royal, I noticed the ALT needle did not move as much when the engine was revved up, like the '66 did. When I asked the service manager about this, he said that was now normal as they'd change the circuit so that all of the current did not go through the gauge, as in the past. A "shunt"-type circuit, he mentioned. That circuit change might have happened the next model year after the referenced TSB mentioned in the video?
To me, the issue of the '60s-era instrument cluster gauge can be more-related to how the circuitry was on the pre-'65 cars. Whether or not they had a real bulkhead connector or just straight circuits where complete wires went through the firewall rather than through a consolidated bulkhead connector.
Personally, I have not yet compared the factory electrical schematic of 1966, to 1970, to 1972, to look for differences. The compare that to the "recommended" ammeter by-pass.
In some related investigations, it appears that all current going through the instrument panel gauge was thr normal way to do things, until it wasn't. And GM went to the "Volts" gauge rather than "Ammeter" in the early 1970s. It was claimed that "Volts" gave a better indication of the charging system, yet I wanted to see IF the alternator/generator was actually charging and the voltage regulator was responding to loads. Which a volt gauge would not indicate. FWIW
In some earlier threads on the ammeter bypass in here, the issue of instrument panel "fires" was more known about by people who had been at dealerships which repaired law enforcement vehicles. With their non-factory electrical equipment added onto the cars and their higher-than-normal alternators to support the additional electrical loads. In a time well before "thump-thump" sound systems and such, and the electrical demands they put on the vehicle hanesses and charging systems.
Now that you've watched the videos, read the prior threads about why this alteration is felt to be needed by some.
Enjoy and welcome!
CBODY67
72RoadRunnerGTX
New Member
That’s interesting, haven’t seen one of those in many years. Interesting too, don’t recall it being available as an over-the-counter service part, available to the general public back then. Recall part numbers typically could only be billed back through factory warranty channels or issued to dealers without billing.
72RoadRunnerGTX
New Member
Stand corrected on that, I recall now, Valiant /6 only in ’60 for the alternator, across the board in ’61 pretty much according the FSMs. Had checked Rock Auto for the application before posting, says alternators on everything in ’60 and generators in ’59.
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57fury440
Well-Known Member
I would not use Rock Auto as an authority on this.
72RoadRunnerGTX
New Member
Authority? no, I don’t, just a quick reference once in a while on parts applications/interchangeability. For that, haven’t run into many errors. Not real surprised they got this one wrong, going back to 1960. Simply shows no reference to generators, only alternator in 1960 and no reference to alternators in 1959, generator brushes only.
Some interesting, perhaps useful info:
The History of Chrysler Alternators, Dodge alternators
A detailed history of Dodge and Chrysler alternator variants, like the round back, square back, and revised square back.
alternatorparts.com
Chrysler's alternators: a major gain over generators
www.motales.com
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