Generator or regulator dying on me (or both)?

Rinke

Well-known member
Hi,
Seems like more people are having some electrical charging issues.

A few months ago I was driving my 64 falcon (inline six, 3 speed manual, stock charging system) on the highway.
When I took the exit the gen light would come on, after a bit of revving the engine, it went out again, but I heared some frantic clicking noises from under the hood (not my valves) for a short while. A month later I drove it a short spin around town, no worries.
This friday I started her up and the gen light stayed on.
I measured the volts on the battery with running engine (choke on, so higher idle) It measured around 12,3 volts.
I believe that is not correct and should read higher, especially since the battery was not fully charged.

I'm suspecting the regulator, or the generator, or both. I had the combo checked at an auto electrical shop when I was restoring the car. That should have been somewhere around 2007 or so. I know the brushes on the generator were not replaced the, due to enough flesh on the brushes, and the shop couldn't order them (Europe cuss cuss). The car is not driven regular, but I have notced a gradual increasing tendency of flickering or brief burning gen light, or staying on for a short while after a (usual)cold start

How can I decide if the generator is suspect or the regulator?
I've checked the shop manual but that's not very clear.

Hope to hear some good advice here.
Grt Rinke
 

bubba22349

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From your description I would first check and test that you have a good ground from the engine to the generator case. as well as from the battery to the engine. This ground test can be done with a simple test light or a volt / ohm meter it you have them. if not examine the case for cleanliness at the mounting bolts you could clean those areas and or could also add a wire from bolt to the engine block if you find you don’t have a good ground. Since you mentioned hearing the clicking in the regulator I would also check all the wiring contections going from the generator terminals to the regulator are they clean, tight, and have continuity?

Because of the regulator clicking if it’s not wiring then it could very well be the regulator contacts inside being dirty or they may be burnt or corroded see regulator testing below.

You can test your generator on the car to see if it’s good. Instead of me typing out the test process check out the below video it’s quite good. Below that is a test for simple regulator. The videos are geared towards English cars so they will look different but the principal is the same on the generator the regulator will look different yet they function the same. Good luck on your testing and if you need more help let us know.

Generator Testing

Regulator Testing
 

Rinke

Well-known member
Hello Bubba and others,

I've finally managed to check all things. I've cleaned the connections to the regulator, checked the other grounds engine to body and engine to battery and regulator to body They were all good, or I cleaned them with a bit of sandpaper until clean, and reassembled with a smear of vaseline.

Started and stil nothing was charging, the battery also indicated 12,5 volts

I did the generator check as shown in the youtube film, with revved engine (no idea about the rpm, but it was loud) I had 0 volts on the generator.
I was kinda scared about overheating the generator. They do not come by easilly here in europe

I think my brushes have gone south.
I could order a 64 generator rebuild set locally with a mustang parts vendor, so that will be in, in a couple of days (Brushes, bearings and the commutator).

Fortunate byproduct, When I removed the generator and spun it by hand, the rear bearing was very noisy.
So I'm calling this a win win situation, fixing my charging problem and rebuilding my generator, Yay :banana:.

Nice corona project .
 

bubba22349

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Excellent diagnoses of the charging problem! The rebuilt generator should get and keep you on the road a long time.
 

B RON CO

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Hi, after you remove the armature take a look at where the brushes rub. This section can show wear and you or an electric motor guy can make it smooth again. It is not a big job but makes a difference in the performance of the generator.
There is nothing wrong with restoring the original parts, but a lot of guys switch to an alternator.
Good luck
 
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