1967 Monaco power issues

[GJS]

Hey all,

Pretty damned sure I already know the answer to this but, I took Bev out last night in a fit of "I need to drive". First time I've rolled in her past dark. All lights appear to be functioning properly, save for the panel dimmer which is on or off. ... thankfully, I can dim all the lights on the car at once by lowering my RPM (!!!!) which is the problem that brings me here.

Without running a meter on it (which I didn't as it was late) I'm assuming my alternator is goofy. I've always gotten a lot of jump in my ammeter but as I never had it out in the dark, I kind of just chalked that up to a crappy ammeter.

Anyway, assuming I'm correct on the alternator, what brand/supplier do you guys trust? I had one rebuilt once for my 68 and the damned thing burned up the wiring harness so I tend to think thats not the way to go. .. but I'm open to being corrected.

Lemme know!

 

[commando1]

New high output alternator + 50 year old wiring = crispy bacon.
Get a replacement alternator no more than 60 amps and a so!id state voltage regulator.

 

[GJS]

New high output alternator + 50 year old wiring = crispy bacon.
Get a replacement alternator no more than 60 amps and a so!id state voltage regulator.

Point taken.

 

[67Monaco]

I'd check all my grounds first. Then regulator. Then alternator....

By pass that ammeter, and put the headlights on relays rather than pull all that juice through the bulkhead.

 

[Snotty]

I had a similar problem. All power through the alternator was gone, running on the battery. I replaced the voltage regulator; took care of the problem for 6 months. Same event happened two weeks ago; it was fun driving home at night with low lights and non-working signals. This time I replaced my alternator; no effect. Thinking it was not necessary, I replace the regulator again; no effect. I was baffled.

I switched to looking at the cables coming from my battery. I actually found a corroded connection; when I jiggled it the car shut down. I corrected that; no effect.

When I say no effect, I mean my ammeter displayed a discharge, every time.

Still confused, I started jiggling the connections to the bulkhead connector of the fire wall. I simply jiggled them, all of them. Looks at the ammeter, viola! It was charging!! Apparently, one of those connectors is bad; I don't know which, but I'm glad I didn't toss the regulator I bought 6 months ago. I expect it to happen again. What I don't know is, should I replace that bulkhead connector, or just the wires?

When I say bulkhead connector, I mean the thing to the right of my booster with the 4 wires going into it.

 

[Polara_500]

This thing? That's not what most refer to as a bulkhead connector, that's the start relay.

This down under here would be where your bulkhead connector is.

 

[Davea Lux]

If the connector to the starter relay is loose or corroded (smaller of the two red wires), that will kill power to the bulkhead connector. I would suggest running a second wire of 10ga from the hot lead of the alternator to the big terminal of the starter relay, be sure it has a fusible link. That will reduce the load on the ammeter by about half so that it does not burn out. Fried ammeters on older mopars were common and could cause a dash fire.

Dave

 

[Big_John]

Hey all,

Pretty damned sure I already know the answer to this but, I took Bev out last night in a fit of "I need to drive". First time I've rolled in her past dark. All lights appear to be functioning properly, save for the panel dimmer which is on or off. ... thankfully, I can dim all the lights on the car at once by lowering my RPM (!!!!) which is the problem that brings me here.

Without running a meter on it (which I didn't as it was late) I'm assuming my alternator is goofy. I've always gotten a lot of jump in my ammeter but as I never had it out in the dark, I kind of just chalked that up to a crappy ammeter.

Anyway, assuming I'm correct on the alternator, what brand/supplier do you guys trust? I had one rebuilt once for my 68 and the damned thing burned up the wiring harness so I tend to think thats not the way to go. .. but I'm open to being corrected.

Lemme know!

Before you start throwing parts at your car, you really should do some simple diagnosing. Doing the mods to bypass your ammeter is a great idea but that isn't your issue and I suggest finding/fixing the problem first.

Easy way to check the alternator and regulator is to remove the field wire from the alternator. Connect your voltmeter to the battery. With the car running, turn all your lights and accessories on. Connect a jumper wire from the field connection to the battery connection on the alternator. Read the voltmeter. It should be in the 14/15 volt range. Only do this long enough to check the voltage. If it's in that range (or higher), it's the regulator. If it's still around 12 volts, it's the alternator.

This is a similar test to the FSM procedure. Snce most of us don't have a carbon pile to add load, all the accessories will add enough load to get a good indication.

 

[FURYGT]

Big John (as usual) is sending you down the correct path.

If your car is a non-A/C car and has the original alternator or a replacement with same amp rating, you likely have a 37 amp alternator. Since you state that you have never driven the car at night before, what you experienced may be normal. At idle with the lights on, your alternator may not be able to keep up with the demand on the battery for the lights and it gets worse when the brake lights are on. Dimming lights, say 20% or so is normal at idle as is a slight discharge reading on the alternator so there may be nothing wrong.

If your voltage regulator is bad or if it is good but is a mechanical voltage regulator the solid state, electronic type of voltage regulator will help your situation. The link below is to what I have been selling for more years than I can remember. Buy it from me or someone else but if your voltage regulator is bad or you just want to improve the diming some, take a look at this:

Mopar Voltage Regulator - Electronic Solid State with Correct Restoration Look 724469250010 | eBay

 

[GJS]

Big John (as usual) is sending you down the correct path.

If your car is a non-A/C car and has the original alternator or a replacement with same amp rating, you likely have a 37 amp alternator. Since you state that you have never driven the car at night before, what you experienced may be normal. At idle with the lights on, your alternator may not be able to keep up with the demand on the battery for the lights and it gets worse when the brake lights are on. Dimming lights, say 20% or so is normal at idle as is a slight discharge reading on the alternator so there may be nothing wrong.

If your voltage regulator is bad or if it is good but is a mechanical voltage regulator the solid state, electronic type of voltage regulator will help your situation. The link below is to what I have been selling for more years than I can remember. Buy it from me or someone else but if your voltage regulator is bad or you just want to improve the diming some, take a look at this:

Mopar Voltage Regulator - Electronic Solid State with Correct Restoration Look 724469250010 | eBay

Thanks for this, man!
It is an A/C car however I can't vouch for the originality of the alternator. I'll run Big John's tests this weekend and see where I'm at.

As you're in CT, It'd be awesome to get the voltage regulator from you. I'll be in touch with the results.

Thanks again!

 

[CBODY67]

The bulkhead connector terminals are an "out of sight, out of mind" situation. The terminals and such probably aren't "bad", just corroded/gunked over time. You should be able to clean them up rather than replace them . . . which can be a better deal in the long run. Initially, they were "dry" or had some anti-corrosion compound sprayed on them OR around the edges of the connector body. Over time, the "oil" dried out and moisture can accumulate with temp swings/variations. Also figure in that some of the terminals might not have had a really tight mechanical connection to start with. "Out of sight, out of mind".

The alternator has diodes which can fail every so often. When they do, the voltage can flow in BOTH directions, which can result in a drained battery. They are replaceable, if you can find replacements. Obviously, they are available as the rebuilders can get them. The alternators are not that hard to rebuild, once you get the front pulley pressed off and back on.

The issue of "dimming lights at idle" is a Chrysler trait, from back then. By "dimming", I don't mean "really dim", but just enough decrease in brightness to notice and NO more. As soon as the rpm comes up off of idle in gear, they are normal again. Never did figure out why Chryslers do this and similar GM cars don't. Possibly a voltage regulator issue? You'll also notice the amp needle move about 1 needle width into "discharge" when this happens. With "load", the regulator catches it, but it'll still be slightly into "discharge" mode.

CBODY67

 

[FURYGT]

Thanks for this, man!
It is an A/C car however I can't vouch for the originality of the alternator. I'll run Big John's tests this weekend and see where I'm at.

As you're in CT, It'd be awesome to get the voltage regulator from you. I'll be in touch with the results.

Thanks again!

67 Factory A/C cars typically had a 45 amp alternator. If you are interested in a voltage regulator and you want to pick it up the price would be $14.00.

 

[GJS]

67 Factory A/C cars typically had a 45 amp alternator. If you are interested in a voltage regulator and you want to pick it up the price would be $14.00.

Your inbox is full .. as was mine. Are you available at all this weekend for a pick up?

 

[GJS]

If the connector to the starter relay is loose or corroded (smaller of the two red wires), that will kill power to the bulkhead connector. I would suggest running a second wire of 10ga from the hot lead of the alternator to the big terminal of the starter relay, be sure it has a fusible link. That will reduce the load on the ammeter by about half so that it does not burn out. Fried ammeters on older mopars were common and could cause a dash fire.

Dave

Hey Dave, what would be the value on the fusible link in this application? This is something I've been wanting to do before she officially goes on the road. As I've said, I've roasted wiring harnesses before and would really like to avoid that or anything like that again.

Thanks!
G

 

[FURYGT]

Your inbox is full .. as was mine. Are you available at all this weekend for a pick up?

I have made space in my in box. Send me a PM.