Generator being back-fed from battery

[dgluvna01]

1964 220Sb

Generator being back-fed from battery. I threw the belt driving waterpump/generator. After switching off the ignition, the circuit between the battery and the generator continues to be energized.

Is this a problem with the ignition switch or is there a relay or other device malfunctioning in the circuit?

[280EZRider]

I believe the relays of the voltage regulator need to be reset; this used to be called "flashing the field." Way back then, it was always necessary when installing a new regulator as well.

[TX76513]

A possible problems would be a back out diode on the diode pack. I am not familiar with your vehicle but the diode pack could be internal or external component.

[Arthur Dalton]

Originally Posted by TX76513

A possible problems would be a back out diode on the diode pack. I am not familiar with your vehicle but the diode pack could be internal or external component.

Diode packs are used in Alternators , NOT generators.
Alt are AC, so they need diodes to convert to DC .. Gen are DC, and being DC output, they need no diodes.

As Rider said, the unit has to be Polarized You jumper across the Bat and Gen teminals of the regulator for a second {Flash second] ..that polarizes the systm and you are done..that has to be done whenever a part is changed in the charging system.

[Mike D]

Generator or alternator? Either way there is usually a "live" battery line to them. The field wire is the controlling influence. All a generator is is an electric motor run backwards.

I had a '54 F100 which you had to pull the battery cable when you changed the spark plugs. The engine was so old and sloppy that when you pulled the plugs the generator would spin the motor backwards! Funnier than hoodoo when a buddy of mine thought he was doing me a favor and swapped in some fresh plugs (the old beast, "Katie-mae", was darned near a two-stroke due to worn rings), called me up just freaking out.

[Arthur Dalton]

Gen ran b/c the regulator points were sticking closed..that is they require polarization. .

Way back before alternators, the test for a generator at the scrap yard was to hook them in reverse polarity to a battery and see if they did spin..if Yes, then we knew it was a good generator.

[Arthur Dalton]

Some old Allis Chamblers tractors used the generator for both the starter and a generator by using a seperate relay to backfeed the generator.
Problem was they had to be belt driven and they were slow turning.
But I had one for years with no problems. Just needed to keep a good belt
on it.

[Chas H]

I've never had to polarize an alternator and don't see why it should be neccessary.
Many years ago I repaired an MV Agusta motorcycle which had a generator/starter. There were 2 belt drives with over-running clutches. The start drive used a small pulley on the generator and a larger pulley on the engine, the generating drive was nearly 1:1.

[Arthur Dalton]

<>

It's not neccessary..an alternator is NOT a generator. A generator gets polarized. An Alternator doesn't...........
Ever buy a regulator for a Generator and see the Polarize Warning Tag???

[TX76513]

Originally Posted by Arthur Dalton

Diode packs are used in Alternators , NOT generators.
Alt are AC, so they need diodes to convert to DC .. Gen are DC, and being DC output, they need no diodes.

Sorry Artie - I said "possible" I have a generator set up that does have diodes and would drain the batteries when not in use as the current would feed backwards from the battery packs.

[Arthur Dalton]

No problem
The confusion comes from the technical difference of an Alt and the old predecessor single winding car Generator. The OP car uses a Generator, not an Alternator..so he has no diode Pak.
One is AC and the other is DC..
The older cars with a standard, 2 brush generator was a dc output and b/c it's output was DC current, it did not need diodes. A alt puts out a sine wave currect and needs a diode pak to convert the output to dc cuz the car uses a 12 Volt Direct Current System.

Goggle Generator Polarize ..there is tons of info on the "hows and whys "
of Polarizing...........

Alt. simply put standard generators out of business b/c they are technically superior... like Electronic ign put point ignitions out of business..they both accomplish the same thing, and the terms are often interchanged, speciialy with power generators.

[Chas H]

Originally Posted by Arthur Dalton

<>

It's not neccessary..an alternator is NOT a generator. A generator gets polarized. An Alternator doesn't...........
Ever buy a regulator for a Generator and see the Polarize Warning Tag???

Nope, never seen a tag like that. Mostly I have generators, starters and alternators rebuilt by a local electrical rebuilder and hardly ever need a regulator. Last one I did was a 1947 Jeep, no tag on the new regulator from the shop.

[Arthur Dalton]

<>

The tags are on the regulators when you buy a new one.

Google Generator Polarity...ton of info and instructions on the preocedure.
Common Knowledge...

[Chas H]

Originally Posted by Arthur Dalton

<>

The tags are on the regulators when you buy a new one.

Google Generator Polarity...ton of info and instructions on the preocedure.
Common Knowledge...

I know all about it. You're not the only one here that has worked on cars.

[Arthur Dalton]

You post looked to me that you were in disagreement ...no problem.