First, this thread was very helpful in troubleshooting my issue. I am posting separately as I didn't want to hijack that thread as the problem is being worked through.

https://www.ford-trucks.com/forums/1...problem-5.html

Yeaterday I drive my truck for a more extended run for the first time since the winter. I noticed my gen gauge was staying solidly in the middle and would drop down maybe an 1/8" with the headlights on. I was having trouble getting my truck restarted and the battery died. I was in a hill so I was able to bump start it and get home. I had the hazards on a for a few minutes so I thought the battery may have been run low.

When I got home I shut it off and then came back to pull it into the garage. Battery was dead. I charged the battery fully and left it on a trickle charger overnight.

After doing some research and reading that thread I learned that it may need to be polarized again after sitting further the winter. So I went ahead and did that.

I then ran a couple of the tests covered in the link above, in particular disconnecting the field wire and checking the voltage at the battery at 1500 RPMs. It was over 8 volts and based on that post had me concerned it might be the regulator. after reading further down it was suggested to hook everything back up and check the voltage again. I decided to do that and take a drive.

The gen meter was now showing a charging state as the RPMS increased. I hooked up a voltage meter and watched the voltage as I drove. At idle the voltage was around 6.6 but would start to slowly fall. I didn't spend anytime trying to find the bottom yet. Initially when I was driving at about 50mph, which I think is around 3000 RPM, it was charging at 8.5 volts and the voltage varied with the RPMs down to 6.6 volts at idle. I was concerned it might be overcharging and the regulator needed adjusting.

I drove about 5 miles and parked it. I came back a little while later and drove to another destination and home. It was now charging at 7.2volts at 63mph and goes down to 6.6 volts at idle. I am guessing the contacts needed some exercising after sitting all winter and cleaned themselves up a bit?! It seemed to self adjust.

In any event it appears to be charging properly now I think unless I am not understanding it. I learned a lesson. Before assuming the worst re-polarize the generator!! Especially if it has been sitting a long time.

I assume everything is operating normally?

Would be cool to have an active volt meter with actual voltage in the truck. Maybe they make a small digital one o can hide somewhere in there....

pics below with comments showing the different states.


Gen needle position at 8.6v and 50ish MPH

8.64 Volts at 50mph

6.62 at idle

Gen needle position at idle 6.6v

Now at 63mph

Gen needle position at 7.2v slightly lower than at 8.6v

 

The generators voltage will vary with engine RPM. The regulator varies the field to compensate/regulate. I'm not sure where you are taking the voltage readings from - between ground and the generator Armature? Or between Ground and the battery terminal? By bypassing the regulator field control, the generator can create as much voltage as it possibly can for the operating conditions and thus exceed 7.5 volts. This is good as it indicates your generator can produce the requisite voltage.

It is not uncommon to need to polarize/flash a generator system after sitting or battery disconnect. It also isn't uncommmon to have to clean the regulator relay contacts similar to how one would clean ignition points (just be careful not to throw it out of adjustment when doing so).

It is also good practice to use a battery tender for extended periods of inactivity. It could also be advantageous to disconnect said battery from a safety standpoint and thus could necessitate polarization at the start of the season.

 

I keep learning...

Those voltage reading are straight off the battery as I am driving. Voltage meter connected directly to the 2 posts.

Over the winter I did in fact disconnect the battery and kept it on a Norco trickle charger for the season. I occasionally took it off for a few days when the cords were in the way of other work. So now I know when I do that or disconnect the battery I need to polarize the generator again.

 

Sounds like its your charging system is working like its supposed to.
I think, the reason you were seeing the 8.5 volts at 3000 RPM wasn't so much about maybe corrosion on your Volt Regulator contacts, but more the operating temperature of the Voltage Regulator itself. The unit is a temperature compensated device which uses bi-metal in the armature hinges. So in cooler temperatures (including the under the hood temperature) it will charge your battery with a higher voltage. Once things start warming up it will charge with a lower voltage to help keep your battery from boiling out. Its because of this that it is so hard to adjust these things in your driveway. They usually use 30 mins of operation as a guide to evaluate and adjust the operation of these units.

You mention about having a 6 volt reading capable voltmeter. No doubt that would be nice. You could simply wire up a Gen fail light. A 6 volt bulb and socket with wires spliced on that connects to your IGN terminal on your IGN switch. The other wire goes to the ARM terminal on your voltage regulator.
You turn you IGN switch on, the bulb lights. When you start the truck and the running revs to around 1500 RPM, the voltage regulator cut out relay contacts connects the generator to the battery, the light will then go off indicating your generator is charging. The light might dimly flash on and off at idle at a traffic light. That will be normal if you do see that. Anyway its just a good indicator when something is really wrong if the light goes on and stays on when the engine is running.

 

Great info. Thanks!!!

Theres an open hole in my dash with a round stainless insert in it which would be a great place for a light. Can I use any switched ignition source or only off the ignition itself? I am not sure there is another source but if so I like using something separate from other switches. Does it need to be fused?

I just finished rewiring my Camaro with multiple switches and BAT connections fused and un-fused so I have that on the brain right now.

 

Westach has 6v gauges, including volts

 

Yes you could use any IGN switch operated 6 volt source as you could wire it into the Accesories side of the switch or the Ignition or coil feed side. Main thing is with your Ignition switch in the Off position the light goes out.
You shouldn't need to fuse it. But you could if you want. Its just a simple switch and bulb circuit only you are getting your bulbs ground through the windings on your generator. When you first turn on your ignition to start the truck the bulb will see a voltage difference and lights. As soon as the truck starts and the voltage regulator sees charging from the generator, the cut out relay pulls and now it will connect the generator to the battery, thus shorting out the bulb and turning it off . If when running there is a problem with the generator, the cut out relay in the voltage regulator opens, and now current from the igntion switch flows through the bulb and finds ground through the generators Armature windings and lights.

 

@hooler1 or anyone else out there!

I installed a bulb as directed. Power to the blower switch wire which is a switched wire, and then a wire to the ARM terminal on the regulator.

The bulb is nice and bright when it starts but only gets dim when it is running. It doesn't go off. What is that telling me and what should I be testing for if anything. Is it possible the wire connection to the ARM is bad? Should I put a meter on it at the light and check the voltage?

The factory battery meter on the dash seems to stay solid in the middle except when the blinkers are on and then it ticks along with the blinkers. It drops maybe a 1/6" when the head lights are on.

I did polarize it again already. Field and batt wires disconnected from the regulator and then touched together and reconnected.

I first installed a 12v light because I didn't have a 6v. It was really dim and then would go off as the rpms came up but I attribute that to a higher voltage bulb.

There are 2 videos attached. 4474 is in the garage with the truck idling and then revving in neutral. 4471 is on the road driving and then pulling up to a stop sign.

thanks!

 

Which bulb # was installed (incandescent, right?)?

 

Yes. 6v 200ma incandescent bulb. This one in a 1/2" barrel and blue lense.

 

I figured it out...

The belt was stretched as far as it would go and was slipping. I put a 1 inch shorter belt on and the light goes off and the meter shows charging. M

I drove it about 12 miles after changing the belt and the light stopped going off again. I tightened the new belt again as it had already stretched and the Gen light starting working again as designed.

This was a great recommendation and I highly recommend it for those running a generator. First, I love that I have a light indicator telling me I left the ignition on. I have left it on while testing wiring etc several times and wound up with a dead battery. Secondly, having a light that clearly shows the state of the charging system is great in conjunction with the factory meter.

I feel much better about driving it longer distances now that I know I can be fairly certain my charging system is functioning properly.

Lastly, any tricks to get the pulley surfaces rougher or something that will reduce the chance of slippage. I think they were stripped and painted and I am thinking the painted surface is too smooth.

 

Great to hear that you find it useful! I think if all you have is an ammeter this is a good addition since 6 volt voltmeters aren't generally available unless you go the Westech route and even while those are great they also are kind of expensive.
I'M sorry I didnt see your earlier post asking why with the engine running you were seeing the light on but very dim. Sounds like you found the reason with the loose belt. You may also see it flicker in stop and go traffic. If so that would be normal because the cut out relay in the voltage regulator is switching the generator in and out of the charging circuit when idling especially with headlights and brake lights on.

Once again Thank You for letting us know its helping you out!

 

So the last few times I drive it the Gen light kept staying on and the gauge did not show it was charging. Aaargh!

I checked the belt and it was fine. I was thinking that the generator was bad now as I have a brand new regulator from Dennis Carpenter. I checked the voltage on the regulator and it wasn't charging at all measuring off the ARM at about 2v. With the power off I had 1.5 volts at the Field and 6v at the ARM although I am not sure I have the ARM measurement recalled correctly. Either way it wasn't charging and the A and F should read 0v with the key off as I understand it.

I have the original regulator that came on the truck and was last used in 1979. Foolishly I figured a new unit would give me more reliability since it is new! I connected the original unit and 0v at the F and A and 6.4 at the Bat with the key off.

Started it up and got it to high idle on full choke which feels about 1500rpm or so and it was charging at 9.5v. Some quick research on here and I learned I needed to bend the spring tab down on the Field and keep adjusting it until I got to 7.2-7.4V. I got it right in that zone and put the cover back on. It is reading about 7.1v now and the Field Jumps between 1.8v-2.25v. The Bat is also at around 7.0 or so and seems to mirror the ARM reading closely.

Hopefully this good old unit from 1979 or earlier will hold out.

It sounds like I have it sorted out?! If I am wrong here and need to do something different or make further adjustments please don't be shy about letting me know.

I did reconnect the Dennis Carpenter regulator and it started working again but was overcharging at 8.5 volts now as opposed to 2v. I don't feel comfortable that it is a reliable piece but I will keep it in the truck as a spare for an emergency and adjust the voltage output if I ever need to use it again.

Lastly, that GEN light is just the BEST. It's how I knew I was having a charging issue as it wasn't going out and just dimming a bit which explains the 2v charge. It can't detect an over charge but that's ok! You should be able to see that on the gauge.


Thanks All!