The Ford Barn

Rex_A_Lott · 12-10-2015, 02:19 PM

My 6V generator is not Model A, like I first thought, but the later Model 46 generator.
A while back I had trouble with the cutout so I replaced it with the Fun Projects Voltage regulator, and all appeared to be working for a while.
Today I noticed when I rev the motor up, the ammeter doesnt show charging any more. I did notice that the ammeter needle just kind of flickers back and forth around zero when its idling, but when the motor revs up it gets steady, but not much (if any ) above zero. I wonder if there is a good way to determine if its charging any at all.
If I turn the lights on, the ammeter shows discharge, which says its not broken, I just wonder if the zero reading is correct.
I tried moving the third brush both down and then back up, but it doesnt affect the ammeter reading much.
I also tried putting a volt meter, on the amps scale, in series with the output of the cutout, but its just a cheapo HF one and it goes apeshit when I try that. I dont have an analog meter to try, not do I have a clamp-on amp meter. I dont have a good cutout to replace the regulator with either.
I have about run out of bright ideas, so I'm looking for suggestions on checking the output of the generator and the accuracy of the ammeter.
I was trying to make sure I was ready for the parade Saturday, so I may just have to charge the battery and run it and hope it doesnt go dead during the run.

AL in NY · 12-10-2015, 02:29 PM

Does the ammeter show discharge right after you start the engine? If so, I feel that the battery is fully charged and your ammeter and generator are working properly. You said you had a voltage regulator installed, then adjusting the third brush doesn't have any effect on the output. I would also check the battery voltage with everything turned off. You should get a reading around 6.2 volts. Now start the engine and check the voltage again. If it's above the original battery voltage, the generator is working. Depending or how discharged your battery may get, the generator output voltage can go as high as 8.0 volts with the voltage regulator.

Tom Wesenberg · 12-10-2015, 02:41 PM

Turn the lights on for one minute, then turn them off and start the engine.
Run it at fast idle (about 800 RPM) and see what the ammeter shows.
It should show at least 5 amps and taper back toward zero after a minute or so.

Also run the engine with the lights on and see what the ammeter shows.

Rex_A_Lott · 12-10-2015, 03:51 PM

With the car just sitting there the battery measured 6.52V with my little cheapo meter. With it running it goes crazy and wont give a steady reading. My guess is the ignition noise is what drives it batty. I hate to know I have to upgrade to a Fluke, I got by without one at home for this long....
I tried Tom's suggestion. Lights on, engine off, the ammeter shows ~10A discharge, and I let it go for over a minute. Start the car, the ammeter behaved pretty much as before...~0 at a fast idle. Never saw that increased charging rate that tapered back off to zero.Turn the lights on and it shows about that same 10A discharge.
Im guessing that the generator is in fact, not charging properly.
I dont like to do this, but I have another car I can rob the generator off of and put it on this one, but that will be a Saturday morning before the parade project, if it happens at all.

Tomy Turbos · 12-10-2015, 04:21 PM

I recommend testing with an inductive analog ammeter made by anyone other than harbor-fright.

These used to be a 'walk in to any parts store and walk out' item, but times have changed.

Just bear in mind that digital ones do not react as quickly as analog but are ostensibly more accurate and that analog ones are most accurate closer to 50% of their range than they are at the ends. By this I mean that a 400A meter will not be very accurate when measuring 10A but it will be very accurate a 200A. This applies regardless of it being digital or analog.

The problem with your HF meter is probably not really that it's an HF meter as much as that it's digital and can't report fast enough to give a stable reading (and its an HF meter).

You gotta remember: There were no digital meters when the car was built.

Fred S · 12-10-2015, 11:50 PM

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I'm in the same boat as Rex_A_Lott. Also have the regulator, and my ammeter only shows zero, or a discharge. I know the battery was really low, and I didn't see it charging, but wasn't really looking. If it did charge it back up, it did it quickly.

I bought a battery hydrometer. 4 balls float on the center cell, and 3 balls float on the other two. Is a hydrometer reliable for checking the charge of a battery?

Y-Blockhead · 12-11-2015, 12:09 AM

Quote:

Originally Posted by AL in NY

I would also check the battery voltage with everything turned off. You should get a reading around 6.2 volts. Now start the engine and check the voltage again. If it's above the original battery voltage, the generator is working.

What Al sez. Simple test that shows the generator is charging. If the generator is maintaining the battery's charge, it's working. Simple as that.

A hydrometer that measures the electrolyte specific gravity is accurate, the floating ball type, not so much. The specific gravity should be ~1.265.

Rex_A_Lott · 12-11-2015, 07:47 AM

Quote:

Originally Posted by Tomy Turbos

I recommend testing with an inductive analog ammeter made by anyone other than harbor-fright.

These used to be a 'walk in to any parts store and walk out' item, but times have changed.

Just bear in mind that digital ones do not react as quickly as analog but are ostensibly more accurate and that analog ones are most accurate closer to 50% of their range than they are at the ends. By this I mean that a 400A meter will not be very accurate when measuring 10A. This applies regardless of it being digital or analog.

The problem with your HF meter is probably not really that it's an HF meter as much as that it's digital and can't report fast enough to give a stable reading (and its an HF meter).

You gotta remember: There were no digital meters when the car was built.

I'm familiar with the analog meters, we have them at work, but I dont have access to one at home. I considered driving up to the back gate and getting one of the guys to bring one out to check it, it would take all of two minutes.
I realize they didnt have digital meters in the 30's when they were new. I'd even go so far as to say that a large percentage of those cars never had an external meter of any sort put on them. I remember we used to pull the battery cable off while it was running, to see if it stayed running, but for some reason I seem to remember that this is not a good idea, so I havent tried it yet.

Gold Digger · 12-11-2015, 08:27 AM

I know its not 100% accurate but I have always loosened the fan belt and jumped a hot wire to the wire coming out of the generator. If it motors the generator its probably charging. I've seen the times that a centrifugal short was present and this didn't work.

Tom Wesenberg · 12-11-2015, 09:24 AM

Here's a good, easy to read analog volt meter that everyone can afford. It's only $$3.89 delivered to your door. Just connect two wires and alligator clips, or use the two clip leads you keep in your Model A tool kit.

You can also buy it in a 0-15 volt style if you use a 12 volt battery.

http://www.ebay.com/itm/1x-DC-10V-An...MAAOxy2BBSUjHt

zzlegend · 12-11-2015, 09:40 AM

Coincidence in this thread? I had a parade last Sunday. Left home, generator charging great as always.

Drove 5 miles but the last 1/4 mile, looked at the gauge and it was on zero.

Would not change when revved up but did show discharge when lights were turned on. Made it thru parade since battery was fully charged. Next day trouble shooting and found generator grounding out. Pulled it apart and found the third brush wire had dropped away from the case and rubbed on the armature and had about 1" of bare wire showing and 2 strands left unbroken.

I replaced with a new wire more solid in strength and tucked up firm. All is good now and back in business.

Parade number 2 this next Sunday. Just my 3 cents. Good luck with yours Rex.

Afordman31 · 12-11-2015, 10:08 AM

We used to disconnect the ground cable while the car was running to see if it was charging, if when disconnected and the car still run the generator was charging.

Tomy Turbos · 12-11-2015, 08:18 PM

A hydrometer cannot tell you the current state of charge. It can give an indication of a battery's ability to take and hold a charge, based on the specific gravity of the electrolyte. It is not and cannot be an exhaustive test of a battery's health.

Assuming that a battery's electrolyte levels are up to snuff and that it's gravity is within spec, one still needs to use a 'toaster' or some other means of load-testing to determine its condition. Believe it or not, the Date Stamp is the first clue.

They don't make batteries like they used to... They also don't make Battery Testers like they used to.

Depending on the source, if a Battery has a 36 month warranty and you're past 24 months, start counting the days 'cause you're going to need one.

Best practice of course is to put in a disconnect if the car (battery) is to be out of service for more than a few weeks. This is the only way to hedge your bet.

Mike V. Florida · 12-11-2015, 11:58 PM

Quote:

Originally Posted by Tom Wesenberg

Here's a good, easy to read analog volt meter that everyone can afford. It's only $$3.89 delivered to your door. Just connect two wires and alligator clips, or use the two clip leads you keep in your Model A tool kit.

You can also buy it in a 0-15 volt style if you use a 12 volt battery.

http://www.ebay.com/itm/1x-DC-10V-An...MAAOxy2BBSUjHt

I used this meter that Tom posted and put it in a cheap craft box.

Rex_A_Lott · 12-14-2015, 05:39 PM

Quote:

Originally Posted by zzlegend

Coincidence in this thread? I had a parade last Sunday. Left home, generator charging great as always.

Drove 5 miles but the last 1/4 mile, looked at the gauge and it was on zero.

Would not change when revved up but did show discharge when lights were turned on. Made it thru parade since battery was fully charged. Next day trouble shooting and found generator grounding out. Pulled it apart and found the third brush wire had dropped away from the case and rubbed on the armature and had about 1" of bare wire showing and 2 strands left unbroken.

I replaced with a new wire more solid in strength and tucked up firm. All is good now and back in business.

Parade number 2 this next Sunday. Just my 3 cents. Good luck with yours Rex.

Saturday morning I finally gave up and just took the generator off my other car and put it on. It worked as expected and we made it through the parade OK.
I know, everybody's thinking " Why the hell didnt you just do that to start with, it took less time than all this typing and posting".

Well, its true, it only took a few minutes, but it just goes against my thinking to take something apart that's working to fix something that's not...it seems like twice the work to me to get it all back working later...and I'm still left with the Model 46 generator that is questionable. I think I need to PM Tom W to see if he is willing to fix it.
Thanks to everybody that offered suggestions.

zzlegend · 12-14-2015, 06:23 PM

Quote:

Originally Posted by Rex_A_Lott

Saturday morning I finally gave up and just took the generator off my other car and put it on. It worked as expected and we made it through the parade OK.
I know, everybody's thinking " Why the hell didnt you just do that to start with, it took less time than all this typing and posting".

Well, its true, it only took a few minutes, but it just goes against my thinking to take something apart that's working to fix something that's not...it seems like twice the work to me to get it all back working later...and I'm still left with the Model 46 generator that is questionable. I think I need to PM Tom W to see if he is willing to fix it.
Thanks to everybody that offered suggestions.

Glad you let us know Rex. Was wondering how you made out. And if it means anything, I am just the same as you. If some thing is working, don't mess with it. But I am sure you will get them both back in working order. Tom W. is the man. Let us know what you find. Or maybe what Tom finds.

Hope your parade went well. Mark.

jfreddie · 12-16-2015, 02:06 AM

Those voltage regulators are fairly expensive...$75 last time I looked. I would take it off and put it aside while you do your troubleshooting. Otherwise you risk frying it and then you might have two problems.

As was mentioned before, loosen the belt so the gen pulley is free and apply battery voltage to the output lead of the gen. If it motors over freely the gen is fine.

Now put the belt back on and start the eng. with it running slightly above idle touch the hot lead to the output post of the gen. The ammeter needle will jump a bit but should settle into whatever charge the third brush calls for and be steady as you increase rpm.

Then install the regulator and follow the adjusting procedure for the third brush and all should be happy.

stouchton · 12-16-2015, 07:18 AM

pull your ammeter and reverse the connections.

If it then does the same thing but in the opposite direction (swings towards charging when discharging) then you know the ammeter is good and generator is not charging (either the generator or the regulator).

As for test equipment, I have good results with a Tenma clamp on DC ammeter.

12-10-2015, 02:19 PM	#1
Rex_A_Lott Senior Member Join Date: Jun 2011 Location: Upstate South Carolina Posts: 794	Generator/Ammeter Question My 6V generator is not Model A, like I first thought, but the later Model 46 generator. A while back I had trouble with the cutout so I replaced it with the Fun Projects Voltage regulator, and all appeared to be working for a while. Today I noticed when I rev the motor up, the ammeter doesnt show charging any more. I did notice that the ammeter needle just kind of flickers back and forth around zero when its idling, but when the motor revs up it gets steady, but not much (if any ) above zero. I wonder if there is a good way to determine if its charging any at all. If I turn the lights on, the ammeter shows discharge, which says its not broken, I just wonder if the zero reading is correct. I tried moving the third brush both down and then back up, but it doesnt affect the ammeter reading much. I also tried putting a volt meter, on the amps scale, in series with the output of the cutout, but its just a cheapo HF one and it goes apeshit when I try that. I dont have an analog meter to try, not do I have a clamp-on amp meter. I dont have a good cutout to replace the regulator with either. I have about run out of bright ideas, so I'm looking for suggestions on checking the output of the generator and the accuracy of the ammeter. I was trying to make sure I was ready for the parade Saturday, so I may just have to charge the battery and run it and hope it doesnt go dead during the run.

12-10-2015, 02:29 PM	#2
AL in NY Senior Member Join Date: May 2010 Location: Southern Upstate New York Posts: 1,160	Re: Generator/Ammeter Question Does the ammeter show discharge right after you start the engine? If so, I feel that the battery is fully charged and your ammeter and generator are working properly. You said you had a voltage regulator installed, then adjusting the third brush doesn't have any effect on the output. I would also check the battery voltage with everything turned off. You should get a reading around 6.2 volts. Now start the engine and check the voltage again. If it's above the original battery voltage, the generator is working. Depending or how discharged your battery may get, the generator output voltage can go as high as 8.0 volts with the voltage regulator. __________________ AL in NY

12-10-2015, 02:41 PM	#3
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: Generator/Ammeter Question Turn the lights on for one minute, then turn them off and start the engine. Run it at fast idle (about 800 RPM) and see what the ammeter shows. It should show at least 5 amps and taper back toward zero after a minute or so. Also run the engine with the lights on and see what the ammeter shows.

12-10-2015, 03:51 PM	#4
Rex_A_Lott Senior Member Join Date: Jun 2011 Location: Upstate South Carolina Posts: 794	Re: Generator/Ammeter Question With the car just sitting there the battery measured 6.52V with my little cheapo meter. With it running it goes crazy and wont give a steady reading. My guess is the ignition noise is what drives it batty. I hate to know I have to upgrade to a Fluke, I got by without one at home for this long.... I tried Tom's suggestion. Lights on, engine off, the ammeter shows ~10A discharge, and I let it go for over a minute. Start the car, the ammeter behaved pretty much as before...~0 at a fast idle. Never saw that increased charging rate that tapered back off to zero.Turn the lights on and it shows about that same 10A discharge. Im guessing that the generator is in fact, not charging properly. I dont like to do this, but I have another car I can rob the generator off of and put it on this one, but that will be a Saturday morning before the parade project, if it happens at all.

12-10-2015, 04:21 PM	#5
Tomy Turbos Member Join Date: Nov 2015 Location: Columbus, OH Posts: 52	Re: Generator/Ammeter Question I recommend testing with an inductive analog ammeter made by anyone other than harbor-fright. These used to be a 'walk in to any parts store and walk out' item, but times have changed. Just bear in mind that digital ones do not react as quickly as analog but are ostensibly more accurate and that analog ones are most accurate closer to 50% of their range than they are at the ends. By this I mean that a 400A meter will not be very accurate when measuring 10A but it will be very accurate a 200A. This applies regardless of it being digital or analog. The problem with your HF meter is probably not really that it's an HF meter as much as that it's digital and can't report fast enough to give a stable reading (and its an HF meter). You gotta remember: There were no digital meters when the car was built. Last edited by Tomy Turbos; 12-11-2015 at 04:15 PM.

12-10-2015, 11:50 PM	#6
Fred S Senior Member Join Date: Nov 2014 Location: Houston, TX Posts: 137	Re: Generator/Ammeter Question Sponsored Links (Register now to hide all advertisements) I'm in the same boat as Rex_A_Lott. Also have the regulator, and my ammeter only shows zero, or a discharge. I know the battery was really low, and I didn't see it charging, but wasn't really looking. If it did charge it back up, it did it quickly. I bought a battery hydrometer. 4 balls float on the center cell, and 3 balls float on the other two. Is a hydrometer reliable for checking the charge of a battery?

12-11-2015, 08:27 AM	#9
Gold Digger Senior Member Join Date: Nov 2011 Location: Arkansas & Alaska Posts: 645	Re: Generator/Ammeter Question I know its not 100% accurate but I have always loosened the fan belt and jumped a hot wire to the wire coming out of the generator. If it motors the generator its probably charging. I've seen the times that a centrifugal short was present and this didn't work.

12-11-2015, 09:24 AM	#10
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: Generator/Ammeter Question Here's a good, easy to read analog volt meter that everyone can afford. It's only $$3.89 delivered to your door. Just connect two wires and alligator clips, or use the two clip leads you keep in your Model A tool kit. You can also buy it in a 0-15 volt style if you use a 12 volt battery. http://www.ebay.com/itm/1x-DC-10V-An...MAAOxy2BBSUjHt

12-11-2015, 09:40 AM	#11
zzlegend Senior Member Join Date: May 2010 Location: Reseda, Calif. Posts: 2,188	Re: Generator/Ammeter Question Coincidence in this thread? I had a parade last Sunday. Left home, generator charging great as always. Drove 5 miles but the last 1/4 mile, looked at the gauge and it was on zero. Would not change when revved up but did show discharge when lights were turned on. Made it thru parade since battery was fully charged. Next day trouble shooting and found generator grounding out. Pulled it apart and found the third brush wire had dropped away from the case and rubbed on the armature and had about 1" of bare wire showing and 2 strands left unbroken. I replaced with a new wire more solid in strength and tucked up firm. All is good now and back in business. Parade number 2 this next Sunday. Just my 3 cents. Good luck with yours Rex.

12-11-2015, 10:08 AM	#12
Afordman31 Senior Member Join Date: May 2010 Location: Michigan Posts: 580	Re: Generator/Ammeter Question We used to disconnect the ground cable while the car was running to see if it was charging, if when disconnected and the car still run the generator was charging.

12-11-2015, 08:18 PM	#13
Tomy Turbos Member Join Date: Nov 2015 Location: Columbus, OH Posts: 52	Re: Generator/Ammeter Question A hydrometer cannot tell you the current state of charge. It can give an indication of a battery's ability to take and hold a charge, based on the specific gravity of the electrolyte. It is not and cannot be an exhaustive test of a battery's health. Assuming that a battery's electrolyte levels are up to snuff and that it's gravity is within spec, one still needs to use a 'toaster' or some other means of load-testing to determine its condition. Believe it or not, the Date Stamp is the first clue. They don't make batteries like they used to... They also don't make Battery Testers like they used to. Depending on the source, if a Battery has a 36 month warranty and you're past 24 months, start counting the days 'cause you're going to need one. Best practice of course is to put in a disconnect if the car (battery) is to be out of service for more than a few weeks. This is the only way to hedge your bet. __________________ There are only two kinds of cars: Those that need fixed and those which are going to.

12-16-2015, 02:06 AM	#17
jfreddie Senior Member Join Date: Jan 2015 Location: anchorage, alaska Posts: 117	Re: Generator/Ammeter Question Those voltage regulators are fairly expensive...$75 last time I looked. I would take it off and put it aside while you do your troubleshooting. Otherwise you risk frying it and then you might have two problems. As was mentioned before, loosen the belt so the gen pulley is free and apply battery voltage to the output lead of the gen. If it motors over freely the gen is fine. Now put the belt back on and start the eng. with it running slightly above idle touch the hot lead to the output post of the gen. The ammeter needle will jump a bit but should settle into whatever charge the third brush calls for and be steady as you increase rpm. Then install the regulator and follow the adjusting procedure for the third brush and all should be happy.

12-16-2015, 07:18 AM	#18
stouchton Senior Member Join Date: Jun 2013 Location: Pottstown, PA Posts: 342	Re: Generator/Ammeter Question pull your ammeter and reverse the connections. If it then does the same thing but in the opposite direction (swings towards charging when discharging) then you know the ammeter is good and generator is not charging (either the generator or the regulator). As for test equipment, I have good results with a Tenma clamp on DC ammeter.