generator problem?

[dacci]

I made 3 measurements of the voltage produced by the generator, and I don’t think that it should work there.

first measurement

on the running car, he threw off the terminal and measured it. gives 19.86 and sometimes drops to 17.
if you return the terminal to its place, then in working condition it will give out 16v

on this sensor I take measurements at 2 ends, the difference in voltage is also not very visible.

Do I understand correctly that the voltage is not rectified to working 14V. the battery is being recharged.

Where to look to solve this problem?

 

[bronze turbine]

First off, I don't think you should take a battery terminal off the battery while the car is running. I can't think of any reason to do that. I think the battery should read about 13V when the car is not running and about 14.3V when the car is running. If like around 11V or so when it's running, I would guess the alternator or voltage regulator might be bad. Oh, and if you measure the voltage at the ballast resistor, depending on which side you measure, it will be lower when the car is running because that reduces the voltage so you don't burn up the ignition system. I'm no genius when it comes to auto electrical systems, but I think these are the basics. Someone correct me if I'm wrong.

 

[bronze turbine]

Just to add to my last message, I think the reading on your meter is sky-high because you have the terminal off the battery therefore no load on the alternator. I don't think that's too good for the electrical system.

 

[1970FuryConv]

If you're voltage regulator was working properly, charge from the alternator would be limited to 15 V or less. The ballast resistor can reduce voltage, but it can't increase voltage.

I agree that voltage should be tested at the battery with both terminals connected. It should be somewhere between 13.5 V and 15 V with the car running. A 2nd test is to connect one lead of the voltmeter to the output stud of the alternator and the other lead to the negative battery terminal. If everything is working properly, the voltage should be in the same range. If not you may have some resistance in the system between the alternator and the battery.

Voltage can go sky high, like your reading, if the voltage regulator has an internal short. This was a particular problem on the one-wire mechanical voltage regulators through 1969. I suggest replacing the voltage regulator and performing the 2 tests above to see if you can get your charging system under control. Putting out 19 V over a long period of time can damage wiring and components, which are not made to handle that much voltage.

 

[Davea Lux]

If the electronic voltage regulator is still working, you are very lucky. Usually if a battery terminal is disconnected with the engine running, the regulator will burn out instantly. Remove the regulator and clean the mount points on the firewall, it needs a good ground. While you are at it, check the circuit board on the back of the regulator for a burnt spot, if you see any charred area, the regulator is dead.

Dave

 

[dacci]

First off, I don't think you should take a battery terminal off the battery while the car is running. I can't think of any reason to do that. I think the battery should read about 13V when the car is not running and about 14.3V when the car is running. If like around 11V or so when it's running, I would guess the alternator or voltage regulator might be bad. Oh, and if you measure the voltage at the ballast resistor, depending on which side you measure, it will be lower when the car is running because that reduces the voltage so you don't burn up the ignition system. I'm no genius when it comes to auto electrical systems, but I think these are the basics. Someone correct me if I'm wrong.

when the terminals are dressed in the normal state, it gives out 16V. this confused me, without a load of 20V, this should not be because it turns out that the generator produces a lot and the battery is being recharged and this will disable it. That's why I'm trying to figure out at what stage the voltage regulation should go through.

what is the white ballast that I measure responsible for?

there is also a steel ballast on the body from which the wire comes from the generator, what is it responsible for?

 

[dacci]

If the electronic voltage regulator is still working, you are very lucky. Usually if a battery terminal is disconnected with the engine running, the regulator will burn out instantly. Remove the regulator and clean the mount points on the firewall, it needs a good ground. While you are at it, check the circuit board on the back of the regulator for a burnt spot, if you see any charred area, the regulator is dead.

Dave

The engine is running. Then one terminal is removed from the battery. If the engine continues to run stably, then the generator and relay-regulator are working. The first consumes electricity from the ignition and other vehicle systems, and the second regulates the voltage of the on-board network. If, after removing the terminal, the engine immediately stalls, it is concluded that the generator or relay-regulator is faulty.

 

[Davea Lux]

when the terminals are dressed in the normal state, it gives out 16V. this confused me, without a load of 20V, this should not be because it turns out that the generator produces a lot and the battery is being recharged and this will disable it. That's why I'm trying to figure out at what stage the voltage regulation should go through.

what is the white ballast that I measure responsible for?

there is also a steel ballast on the body from which the wire comes from the generator, what is it responsible for?

The white ballast on the hood hinge is for the ignition. This cuts 13v from battery to about 8 volts when the car is running, key on, engine not running; you should get about 8 volts at the double wire connection. The start circuit on the double wire connection on the output side of the resistor provides 13 volts (battery voltage) to the coil on start up (key in start position) to increase spark. What year car is this? It looks to have an after market electronic voltage regulator which would not be stock on a pre '70 vehicle. You should be getting a reading of about 13 volts from where you are testing on the ballast resistor. Check the battery in your voltmeter, if it is about dead you will get readings that are way off. I need to see a photo of the "steel" ballast, you might be looking at a condenser. If this is a generator equipped car, a condenser was used on the field terminal for static suppression on radio equipped cars. An electronic regulator will not work with a generator, only an alternator.

Dave

 

[dacci]

The white ballast on the hood hinge is for the ignition. This cuts 13v from battery to about 8 volts when the car is running, key on, engine not running; you should get about 8 volts at the double wire connection. The start circuit on the double wire connection on the output side of the resistor provides 13 volts (battery voltage) to the coil on start up (key in start position) to increase spark. What year car is this? It looks to have an after market electronic voltage regulator which would not be stock on a pre '70 vehicle. You should be getting a reading of about 13 volts from where you are testing on the ballast resistor. Check the battery in your voltmeter, if it is about dead you will get readings that are way off. I need to see a photo of the "steel" ballast, you might be looking at a condenser. If this is a generator equipped car, a condenser was used on the field terminal for static suppression on radio equipped cars. An electronic regulator will not work with a generator, only an alternator.

Dave

car of 1966, but apparently they themselves installed electronic ignition on it.

 

[Davea Lux]

car of 1966, but apparently they themselves installed electronic ignition on it.

'66 can be converted to electronic ignition and it will have an alternator. Usual conversion to electronic ignition also requires an electronic voltage regulator. If your volt meter is accurate, the voltage regulator is probably fused or shorted out in the full charge position. Start by replacing that. Remember that you should never unhook a battery cable with any electronic components, especially the regulator when the engine is running.

Dave

 

[1970FuryConv]

If the electronic voltage regulator is still working, you are very lucky. Usually if a battery terminal is disconnected with the engine running, the regulator will burn out instantly. Remove the regulator and clean the mount points on the firewall, it needs a good ground. While you are at it, check the circuit board on the back of the regulator for a burnt spot, if you see any charred area, the regulator is dead.

Dave

If the fusible link burns apart because of overcharge, and I didn't repair the wire, but put in a new voltage regulator and started the engine with jumper cables, would the same VR burn out apply?
It's a 1990 pickup so it still had power to ignition. Suspect field - short to ground or internal short to ground in computer.

 

[Davea Lux]

Unless the vehicle has a larger than stock alternator, the fusible link should no burn out because of an overcharge situation. Normally, the fusible link is supposed to protect the wiring harness from a direct short someplace. An alternator that is shorted to ground could cause this. Suggest taking it off and having it tested before proceeding further. Open circuits are very hard on electronic regulators, so the new one might be suspect, but repair the fusible link and test the alternator. After that is done you can test the charging circuit to see if the regulator is working.

Dave

 

[1970FuryConv]

The alternator tested good at Advance. I'll have to report back

 

[1970FuryConv]

I repaired the charge output wire.
I also cut off the alternator connector and wired individually to the alternator.
Computer is controlling voltage fine, 14.21V at idle
DD, drove it to work today