Bypassing Amp. Gauge?

[Edlanta]

The lights are dim on my 67 coronet and I am measuring roughly 12.5 volts at the battery. I have cleaned the bulk head connectors, checked the wiring and grounds. Through research I have heard that all the power generated by the alternator 1st go's through the bulk head, then the amp gage then back through the bulk head to the battery. I have also heard that when the gages get old they can develop enough resistance to create charging system problems and may even cause fire.
Can I simply disconnect the original gage and splice the 2 wires together or put an aftermarket in its place?
Thanks!
ED.

[John Kunkel]

Bypassing the ammeter takes care of the problems associated with it but it doesn't address the problem of the bulkhead connector. The link below shows how to eliminate both problems:

http://www.madelectrical.com/electri...p-gauges.shtml

[Edlanta]

Thanks John!
I'll change things over this weekend and see what happens!
ED.

[ehostler]

Dim headlights can be caused by a couple of things. Odds are, bypassing the alt gauge will NOT resolve the problem.

The problem is most likely caused by low output (at idle) from your alt. You can either put a smaller pulley on the alt or replace it with on that has a higher output at idle.

You could be looking at the fact that you only have weak sealed beam headlamps and you are comparing them to the output of newer cars.

The most common cause has to do with the old wiring in the entire headlight system. Look at the small diameter of the wires and the major amount of resistance in the headlight swtich.

If you are not concerned about originality, I would rewire the headlight circuit, to use relay and 10g wire.

Here is a great diagram of how to do this.

[dkn1997]

I feel that you should be shooting for at least 13/13.5v at idle.

definately make all of the suggested changes. eliminating the bulkhead connector, relaying the headlights and a decent alt will amaze you.

no need to go crazy on the amps, just make sure that it charges well at idle. that means an alt from a newer vehicle. even a rebuilt oem muscle era alt, no matter the size, will probably not charge very well at idle.

[hedgehog]

Check for voltage drop, that will tell you if there is a problem with that circuit. Use a voltmeter, check battery voltage. Then place the neg voltmeter lead on the neg battery and the pos lead on the alternator wire. If the voltage is more than .5 volts less than battery voltage then there is a problem.

[Blygy]

SSOOOOO .. what size of fuse do you recommend for the headlight setup.

And do the newer Alts have the same mounting setup as the older ones or do we need to make new brackets????

Also why wire to the alt and not to the battery..Wouldn't wiring to the alt give inconsistant voltage @ idle vs cruising RPM??

Blygy

[Edlanta]

Thanks for all the good advice. Since reading about all the resistance generated in the amp gage I am going to start by rewiring that portion of the electrical system. Hopefully that will cure my charging problems. I'll follow up with the headlight circuit. I plan on driving this beast and want every part of it to perform at its best. Thanks again for taking the time to reply!
ED.

[dkn1997]

And do the newer Alts have the same mounting setup as the older ones or do we need to make new brackets????

I know that the newer mopar denso alts have the same mounting as the old ones.

On the bottom, the old style alts have a threaded ear that the adjustment bolt threads into (through the slotted bottom bracket) the newer alt has the ear, but it is just a hole. just need to get a nut that fits your original adjustement bolt.

I also needed to trim just a bit off my factory spacers.

except for adding a nut and trimming two spacers with a dremel, it is a bolt in deal.

[ehostler]

Just wanted to add... Since that lower bolt is the one that you tighten, while holding the alt at tension, it's kind of hard to have a hand on the bolt, a hand on the nut and a hand on whatever you use as a tensioner (unless you have help). That being the case, I recommend that you JB Weld the nut onto the back of the ear and let it harden, before you go to install.

[darren509]

Are you reffering to the newer Mopar denso alt. as the same one you installed into your ride a while back, ; the 100 AMP ? If so , if I were to get one where do I go and what to ask for ?

[ehostler]

We got the ND alts from a company that was selling them on ebay. They were pulled from conversion vans that were being converted into ambulances. I don't think that they have any left.

These are the ND alts that are on the Rams, Dakotas, and Jeeps.

[darren509]

What about the 100 AMP unit from MAS Racing part # 7509RC ? I see it advertised in the Mopar Muscle....

[ehostler]

They have no description other than the AMPs. Based on the pic, it is an early alt that has the 100 AMP kit installed in it. Those kits are no good at idle. It will actually produce less current at idle, than your existing alt. Once you get up to about 1,200 RPM, the alt will start producing viable current.

The ND alt produce great current at idle. If you go to the parts store, the alt for a '96 Ram with A/C and towing package, is about 110 AMP. Instead of a special field connector on the back, it just uses to terminal lugs. It will run just over $100 after core exchange (most parts stores don't care that you are not giving them the same style alt in exchange).

The only thing that will need to be done to the alt that I mentioned, is it will need the correct pulley installed. This can be had from most any GM alt.

[darren509]

After going to madelectrical.com and looking at diagram B im confused as to how to hook up a volt meter and still following those steps. Any help ?

[ehostler]

For the volt meter, connect the (+) side to any switched hot in the system and the (-) side to ground.

[Edlanta]

The schematic from mad shows the output from the alternator running straight to the battery (starter relay). Does the output need to run thru the regulator on the firewall 1st???

[ehostler]

I haven't looked at the MAD website. Since you appear to be talking about a normal, external regulator, the hot from the Alt never runs through the regulator.

The regulator gets it's current from IGN 1 of the ignition switch.

The HOT from the alt should go to the starter and then to the batterry. I then leave the original hot leads in place (one from the alt to the #1 splice and the other from the battery to the relay to the AMP/ALT gauge). Once the power is in the vehicle, you can either bypas the alt gauge or run through the alt gauge. By doing it that way, the current is allowed to go the path of the least resistance and divide the power input to two different wires. This allows the exisiting wires to safely pass more current.

[Edlanta]

Thank-You "VERY MUCH" Mr. Hostler!
This web site has helped me tremendously with my projects.
ED.