Ammeter Battery overcharge

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Thanks Kit. Gimme 10. Gotta connect a few wires and will report back.
So measure voltage at batt posts and then measure batt + to ign term on VR. The batt voltage should be higher by only a few tenths correct?
 
The new regulators control the signal to the alternator through the ground side of the circuit. It is very important that you have a good regulator case to body and engine ground. Otherwise the regulator will cause the alternator to overcharge.
 
4spdragtop said:
Thanks Kit. Gimme 10. Gotta connect a few wires and will report back.
So measure voltage at batt posts and then measure batt + to ign term on VR. The batt voltage should be higher by only a few tenths correct?
Click to expand...
The voltage to ground at the IGN terminal of regulator is what the regulator regulates. It should be around 13.8V, but with temperature compensation, in cold weather a few tenths higher, and when hot a bit lower. The battery has a slightly higher voltage, because it is tied closer to the alternator output, with small voltage drops back to IGN terminal. The current on IGN feeds the ignition coil, and alternator field. That current varies with RPM, and other electrical loads and can range from a few amps to several.
So back to the original question, at battery voltage should be 13.8V to 14.5V max, better is below 14V when warmed up, 15V will cook a battery on a long trip.

As Mike says ground is important, with bad ground at regulator, regulator sees less voltage, so it increases, to the voltage it wants to see. The best way to check grounds is under load, check voltages between grounds. Battery (-) to engine, alternator to engine, regulator case to chassis, and chassis to engine, good is 0.1 V or less.
 
Ok, found some time to do more tests. This is using the old "looks" VR but the modern guts. And my original 1 field alternator
1. Batt -ve to IGN on VR with car running 14.1 V (you mentioned 13.8 V??)
2. Batt -ve to +ve with car running 14.2 V
Car still will not idle. Amp gauge nearly pegged.

Other tests I performed with car off and key off.
1. Batt -ve to Alternator case, there is continuity so good ground right?
2. Field terminal on alternator(where green wire connects to) to alternator case, continuity with 1.2 ohm resistance( resistance steadily dropped from 25 then down to 1.2)
3. Battery -ve to +ve 12.9 V. So battery is good
4. Battery -ve to VR mount bolts, continuity. But again resistance steadily dropped and stayed at 0.9 ohms.
5. Batt +ve to green field terminal on VR 12.5V
6.Battery +ve to IGN terminal on VR 13.1 V

Car running tests
1. Batt +ve to blue IGN VR terminal 0.1 V
2. Batt +ve to -ve 14.2 V

Sorry I cant decipher these tests, but something aint right. Ive cleaned up some of the wiring. Replaced blower motor wire right to the bulkhead connector. Had all 3 plugs removed from bulkhead connector and all look good. Small nail file and electrical cleaner to them.
2 out of the 3 8 plug connectors at bulkhead are new M & H. Third connector is in good shape with no melting. Under dash in real nice shape BUT a pain in the arse as its an AC car.
Any advice is appreciated and thanks for your patience LOL

Cheers
Steve
 
Your readings seem good, a little high but that might be your meter. Batteries typically measure 12.6 to 12.7V unloaded. Your battery at 12.9V seems high, so your meter could be off about 0.2V to 0.3V. That puts your reading in the good zone.

Measuring continuity for grounds does not work well, meters do not measure low Ohms well. That is done as suggested earlier by measuring voltage at grounds with car running and electrical loads on.

The amp gauge may read high if the nuts are loose on the gauge terminals. Make sure you disconnect battery before working on that. There is likely a shunt that is in parallel with meter. Shunts are very low resistance, poor connection there can easily make gauge read high and give voltage drop. Many eliminate the gauge by putting both red and black on one stud. Insulators on studs shrink and disintegrate, resulting in loose connections.
I am no expert on this for a 67, others may chime in with better help. Neither connection is grounded, doing so will short circuit power ... best to check well before hooking battery up.
 
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Thanks Kit. One of the things I haven't checked is the gauge itself. As i mentioned its an ac car with radio so lots of obstacles to get to the gauge.
The bulkhead and connectors under the dash appear in real good shape.

One other test you mentioned earlier I performed on original VR. 7.7 Mega Ohms with everything disconnected.

Thanks again

KitCarlson said:
Your readings seem good, a little high but that might be your meter. Batteries typically measure 12.6 to 12.7V unloaded. Your battery at 12.9V seems high, so your meter could be off about 0.2V to 0.3V. That puts your reading in the good zone.

Measuring continuity for grounds does not work well, meters do not measure low Ohms well. That is done as suggested earlier by measuring voltage at grounds with car running and electrical loads on.

The amp gauge may read high if the nuts are loose on the gauge terminals. Make sure you disconnect battery before working on that. There is likely a shunt that is in parallel with meter. Shunts are very low resistance, poor connection there can easily make gauge read high and give voltage drop. Many eliminate the gauge by putting both red and black on one stud. Insulators on studs shrink and disintegrate, resulting in loose connections.
I am no expert on this for a 67, others may chime in with better help. Neither connection is grounded, doing so will short circuit power ... best to check well before hooking battery up.
Click to expand...
 
Ok cleaned up bulkhead connectors. replaced gray coil wire and cleaned up fusible link. Very good ground at VR mount
Now no start. No headlights.
I have pwr thru fusible link.
Pwr to batt stud on alternator.
ALSO continuity from batt + to alternator case?
Now what?
This was with replica modern style VR.
Im putting old VR on to see what happens.
 
Did you tighten female terminals in bulkhead? They are likely brittle and need to be replaced. Have you checked for voltage at fuse box? Just probe around all fuse ends, some will have power without key on. If nothing there, then bulkhead might be connections open.

Check amp gauge terminals, see if they are loose. Disconnect battery first. That A/C vent assembly comes off with a couple nuts using 7/6" deep well socket.
 
4spdragtop said:
Ok cleaned up bulkhead connectors. replaced gray coil wire and cleaned up fusible link. Very good ground at VR mount
Now no start. No headlights.
I have pwr thru fusible link.
........................
Click to expand...
As in nothing working in the interior or it cranks but no start?
 
4spdragtop said:
Thanks Dave, No pwr to interior (radio signal headlights)and no crank.
Hazards work
Pwr going thru fusible link nto bulkhead.
Click to expand...

I'm thinking you need to go back through the bulkhead connector. Kit made the point to close up the females to get them tight on the males.
 
I just found this thread...

Steve, check for power into the bulkhead from the main alternator wire in the center bulkhead with the large black 12 Gauge wire going in.

Then check for power to the fuse block at the Battery Feed and Accessory Feed input then output...

67 Elect Wires 01.jpg


67 Elect Wires 02.jpg


67 Elect B01.jpg


67 Elect B02.jpg
 
Excellent information, even if it is 2x.

Is there a page that shows igniton switch?
 
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Thanks all I have wiring diagram with switch.
I tested fusible link between battery and bulkhead with bulkhead under hood disconnected. There is power that far.
If im right, the power goes from there to ammeter and back out ammeter (now black wire) to bulkhead connector. When I chk for power at black wire bulkhead connection there is no power. To me that means an interruption/break at ammeter or direct connections?
 
Ok so lets assume the ammeter is toast.
Are fluctuating gauge, lousy idle and now no interior pwr symptoms of a bad ammeter?
The no interior pwr is a new gremlin.
Frustrating, several.connections were replaced and/or wire wheeled, soldered spotless.


Why do I get continuity from alternator case to battery positive?

If it is ammeter and/or connections is there a way to bench test a replacement gauge before installing?

Thanks again all
 
4spdragtop said:
Ok so lets assume the ammeter is toast.
Are fluctuating gauge, lousy idle and now no interior pwr symptoms of a bad ammeter?
The no interior pwr is a new gremlin.
Frustrating, several.connections were replaced and/or wire wheeled, soldered spotless.


Why do I get continuity from alternator case to battery positive?

If it is ammeter and/or connections is there a way to bench test a replacement gauge before installing?

Thanks again all
Click to expand...

I am not sure how you are measuring continuity of alternator case to battery. That might indicate a load, or short. Not much current flows in a meter continuity test, so result can be uncertain. If you detatched output lead from alternator (1st disconnect - lead from battery), insert test light between alternator output and power lead, reconnect battery ground lead. If light lights, there is a short in alternator. The short may be at insulator at output, or bad diodes in alternator. If no light, place test light between battery terminal and ground cable, if light lights the car has a short. First place to look is at amp meter red and black. I think bad insulators can make a fault to instrument housing.

You are going to have to bite the bullet, remove battery cables, take instrument cluster out and fix ammeter.

I am doing the best I can to help, but it is hard to do without being there.
I found this, but have not done it myself. Bullet-Proof Your Ammeter (A 'How To') - DodgeTalk : Dodge Car Forums, Dodge Truck Forums and Ram Forums
 
Thanks Kit, believe me the help Is much appreciated.
If i pull cluster and ammeter I will probably do the mad upgrade. I bought a Demon IVR from Redfish on here a while back, plus when dad had his.tach redone it wasnt calibrated properly so reason #2 to pull cluster.
Shitty as anytime you pull the inst bezel yer playing roulette.
 
4spdragtop said:
Why do I get continuity from alternator case to battery positive?
Click to expand...

Try disconnecting the ground wire from the battery and try that again...

May be grounding through another curcuit that just has resistance to ground, not an open switch...
 
Will do Karl. Its like frickin accupuncture with damn multimeter probes.
I wonder if ammeter fluctuating was a sign it was on its way out?

Another question. ..if I do MAD upgrade, I could do it without removing inst bezel correct? I could snip both red and black wires and connect/loop.closer to bulkhead connector correct?
 
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