Generator Third brush Adjustment

[Capt Kirk]

I kinda though this might happen in reviving an old thread. Karl's last post was in April and I'm guessing he got his problem solved. I will send tom a PM. Kirk

[Capt Kirk]

Thanks JSeery...I don't drive the car much but I know what you're saying and I was worried about it too. Funny (but not so much) you should mention the lights. I don't have headlights anymore as of recently. Guess I'll be shopping for some bulbs soon too. Should I be talking with Tom regarding a new cutout?

[Brian]

Modern electronic solution to a perceived problem! Running during the day with headlights on? w/o cooking out the electrolyte from overcharging?
The problem is NOT the generating system. It is the owner/operators lack of understanding of how the system works.
It's an old Ford. Things are simple; during the day, whilst toddling down the road, all the battery needs to supply is sufficient current to feed ignition; what else is there? Accordingly, all the generator needs to supply is sufficient current to compensate; 2 amps?
Come nite time, lights are on, current demand off battery is more [ ignition plus lites] so the generator output must be increased to suit. Move the 3rd brush down. Look at the ammeter. That's why it's there. you want to have it showing the same 2-3 amp charge with headlights on.
You are the regulator of current output by moving the third brush to suit the load on the battery. Sigh.

[ford38v8]

Originally Posted by JSeery

I would get something fixed to correct this condition as quickly as possible, it is bound to damage the battery charging it at 9 volts. It will take a toll on the rest of the car as well, lights etc.

One way to go is an electronic cutout, but I would start by backing the charge rate on the generator down. There is no reason to be running it at this level. 10 amps (ever if it's a guess with the stock gauge) is way to much, should be right at 0 on the charge side slightly.

I agree, but will add one detail: When you start the engine, you draw the battery down a bit, especially if it takes more than a couple of cranks. Your ammeter will show a couple points into the charge till you've driven sufficiently to recharge, at which time the needle will fall back to normal. If this recharge process takes more than 15 minutes, you may have a problem.

[Capt Kirk]

Originally Posted by Brian

Modern electronic solution to a perceived problem! Running during the day with headlights on? w/o cooking out the electrolyte from overcharging?
The problem is NOT the generating system. It is the owner/operators lack of understanding of how the system works.
It's an old Ford. Things are simple; during the day, whilst toddling down the road, all the battery needs to supply is sufficient current to feed ignition; what else is there? Accordingly, all the generator needs to supply is sufficient current to compensate; 2 amps?
Come nite time, lights are on, current demand off battery is more [ ignition plus lites] so the generator output must be increased to suit. Move the 3rd brush down. Look at the ammeter. That's why it's there. you want to have it showing the same 2-3 amp charge with headlights on.
You are the regulator of current output by moving the third brush to suit the load on the battery. Sigh.

I agree with most of what you're saying about demand and what-not but I don't believe that someone's grandma popped the hood, removed the band and slid the 3rd brush if she got caught by nightfall shopping at the Alpha Beta store. I guess the third brush regulates current but if the cut-out fails, the 10 amps of current is going to the battery whether it needs it or not...right?

[Brian]

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If the cutout fails, it sticks shut, and the ammeter will record a massive discharge upon turning engine off. I bet our grandparents understood what it took to operate a vehicle in their day.
The cut out is exactly that; a cut out; it prevents backflow of current, much the same as a modern day diode. It has squiddly dot to do with regulation of generator output.

[Capt Kirk]

Originally Posted by ford38v8

I agree, but will add one detail: When you start the engine, you draw the battery down a bit, especially if it takes more than a couple of cranks. Your ammeter will show a couple points into the charge till you've driven sufficiently to recharge, at which time the needle will fall back to normal. If this recharge process takes more than 15 minutes, you may have a problem.

I've got a problem then. When cold, it cranks 1 to 2 revolutions before firing. At idle, it's slightly above the zero line (positive charge). Yesterday, it read 10 amps at road speed for the entire drive. I'm assuming my cutout is bad. Yesterday, I drove maybe 15 minutes to a friends house and turned the car off. 15 minutes later, it cranked hard but started. As I run all this through my mind, maybe the Optima was getting 10 amps that it didn't need for those 15 minutes and heated up to the point where a restart when hot was lacking.

[Brian]

So...was the battery hot [boiling]? Sounds to me like you've got a different issue.

[Capt Kirk]

Originally Posted by Brian

So...was the battery hot [boiling]? Sounds to me like you've got a different issue.

It's under the floor and it's an Optima so I don't think it boils per se but I'm sure it can get too hot from over charge.

[JSeery]

Why not back the charge rate back on the generator? Fairly quick and simple!

[ford38v8]

Originally Posted by Capt Kirk

I've got a problem then. When cold, it cranks 1 to 2 revolutions before firing. At idle, it's slightly above the zero line (positive charge). Yesterday, it read 10 amps at road speed for the entire drive. I'm assuming my cutout is bad. Yesterday, I drove maybe 15 minutes to a friends house and turned the car off. 15 minutes later, it cranked hard but started. As I run all this through my mind, maybe the Optima was getting 10 amps that it didn't need for those 15 minutes and heated up to the point where a restart when hot was lacking.

As Brian said, a cutout is simply a one way valve, and regulates not at all. A Fun Projects cut-out is actually an electronic regulator which looks like a period correct cutout. Your zero reading at idle may indicate a generator speed too slow to begin a charge. Your burned out lights may also have been the canary in the mineshaft that you didn't recognize.

[FlatheadTed]

I think it would take the 15 min to recover the OP charge level from starting ,so no over charge ,Use a quality jump cables and run a additnal ground to the back of the starter from the battery

[Capt Kirk]

Originally Posted by Brian

If the cutout fails, it sticks shut, and the ammeter will record a massive discharge upon turning engine off. I bet our grandparents understood what it took to operate a vehicle in their day.
The cut out is exactly that; a cut out; it prevents backflow of current, much the same as a modern day diode. It has squiddly dot to do with regulation of generator output.

Brian, Aren't these cutouts a fairly simple "switch" that essentially tells the generator to stop charging? My generator is charging...too much. Seems to me that it's the job of the regulator (cutout) to figure out what's required under the circumstances. When I've got only engine load on the electrical system and it's charging 10 amps then I think there's something wrong. Sure, I could move the 3rd brush to handle the couple amps required to run the engine but as soon as I fire up the big bass woofers and the 500w amp...the generator isn't going to cut the mustard. My reasoning is based on a battery charger...you can set these to 2 amps, 15 amps...50 amps....at the same voltage. Apparently, my generator is set at 10 amps and that's fine. Battery chargers will reduce the amperage the closer the battery comes to fully charged. A charger likely does this through some modern day regulator. My generator is putting out the amps and the volts...only thing left is regulation of those...I'm guessing.

[Capt Kirk]

Jseery....pm sent

[Brian]

big bass woofers and the 500w amp...the generator isn't going to cut the mustard.
So... you're running 12 volt with a heavy demand on the charging circuit?
Not 6 volt stock?
The regulator is not the cutout. The cutout comprises part of a regulator , along with voltage and current controls.
A 3 brush generator only incorporates a cutout. YOU, via the third brush, regulate the output of generator.

[Capt Kirk]

Brian...I was joking to make a point. The car in question is my avatar. The only music in that car is playing in my head and likely taking necessary amps from other physical motor functions

[JSeery]

Originally Posted by Capt Kirk

Jseery....pm sent

If you sent a PM it didn't come through. Think you are confusing yourself on what is going on here. Your generator is not set properly and the cutout is not going to correct that. Get the generator set properly, very simple to do and if you don't like the new setting move it back. The cutout is a cutout, not a regulator. It works properly when the generator is set properly, it goes not correct for it.

[Capt Kirk]

If the only function of the cutout is to prevent backflow of current after the car is shut off and turning the generator into a motor...then I had things completely screwed up in my mind. I can accept and understand that but I guess I figured things differently. I don't ever remember my dad stopping during out long cross country road trip vacations telling us that he needed to move the third brush because it was getting dark. I was raised up in this car...Hell, I may have even been conceived in it...who knows?

[JSeery]

I'm not a fan of moving it around everyday, but it does need to be set correctly at least once!! You are frying you car parts and battery and all you need to do is set it correctly. No need to mind game this one as it is so easy to perform a real life experiment and see how it works in real time.

[Capt Kirk]

Originally Posted by JSeery

If you sent a PM it didn't come through. Think you are confusing yourself on what is going on here. Your generator is not set properly and the cutout is not going to correct that. Get the generator set properly, very simple to do and if you don't like the new setting move it back. The cutout is a cutout, not a regulator. It works properly when the generator is set properly, it goes not correct for it.

I will go out and set it now. I incorrectly assumed that it was an automatic "on off" switch based on the batteries needs. Now I understand that I can set the third brush to put out a constant amperage based on my driving needs. I don't drive it at night and something has changed with the way it's charging over the years. I will report back in a bit after I make the change.