Flash field on generator

Is there any inline fuses that may have tripped. I had a similar problem many years ago and I needed to have the internal windings restrung / rebuilt. After this procedure my unit ran flawlessly and even above normal spec outputs

Flash Your Generac Portable Generator with a Corded Drill ...

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https://www.youtube.com/watch?v=-LR62sm7USU
Oct 31, 2012 - Uploaded by Generacpowersystems
If your portable generator runs but doesn't produce output voltage, you can use a corded drill to reintroduce ...

Re-energizing Dead Generators - End Times Report

www.endtimesreport.com/dead_gen.html

Follow these steps to flash the generator: Plug the electric drill into the generatorreceptacle. (Cordless drills do not work) If the drill is reversible, move the direction switch to the forward position. Start the generator. While depressing the trigger on the drill, spin the drill chuck in reverse direction.

Generator flashing

www.dieselduck.info/machine/03%20electricity/flashing_generator.htm

To restore the small amount of residual magnetism necessary to begin voltage buildup, connect a 12 volt battery to the exciter field while the generator is at rest, as follows: Remove exciter field leads F+ and F- from the voltage regulator.

Flash A Generator - Davidson Sales Co Power Generation .

Sometimes, after a long period of non use, you need to 'flash the field' of a generator. If your gen is electric start, this should not be the problem. If it is a pull start, maybe so. Go online and see if you can find a schematic of you gen and try to find the field connections. Sometimes just momentarily connecting a battery across the field terminals will do the trick

If we assume for the moment, that the internals of the generator are all ok. This problem is usually caused by not running the unit on load for a long time, a year for instance. During this time the residual magnetism in the field coils will slowly decay. When the unit is running the field coils control the power generated by the main windings. The higher the excitation voltage in the field coils, the higher the voltage generated by the main windings. The field coils are controlled by their magnets which, once a voltage has been generated, they will then self excite themselves.
However, if all of the magnetism has decayed then the field coils cannot generated because they have no excitation to start them off.
What you need to do is to find the field coil windings and while the unit is running with a load plugged in to it, you need to flash a voltage across the field coils.this will excite the field coils, part of that is used to do whats called self-excitation, honest...it is.
If you do this then a 12 volt car battery is a sensible thing to use for a power supply. But, as soon as the field coils start to self-excite then that voltage will increase far beyond 12 vo9lts. That is why you need a good size load connected, As the unit starts to generate then that load will alert you to remove the temporary supply, if you leave it connected the battery acid would rapidly boil and it can split the battery cases. That is why it's called 'flashing' it up. Once generating it wants leaving for a good hour,
If that does not produce results then the fault is deeper and requires testing by a qualified engineer.

With the generator and the regulator on the bike, MOMENTARILY flash the armature connection of the generator with the positive terminal of the battery.

With the generator off the bike, flash the field terminal with the negative side of the battery.

Good Luck
Steve

Hi and welcome to FixYa. I am Kelly. When a brush type generator sits for a long period of time they sometimes require a field flash to get the generator producing power again. You can do this with something as simple as a 9V battery (difficult method) or a hand drill. I would recommend the hand drill. What you do is start the generator with the drill connected and the output power turned on. Once up to speed turn the drill by hand rapidly several times. (This generates a field) Mind you the drill will take off at normal speed once the generator starts producing power so please don't have a death grip on the drill chuck as you rotate it. The bigger the drill the better (more field power)

If this does not get you going again just respond here and there are other ways we can get your generator to start putting out power again. I doubt given your usage that there is any real problem with the circuitry.

Thanks for choosing FixYa.

Kelly

From the Service Manual. You can obtain one relatively inexpensive from Promanuals.net. Here is a direct link for your truck.

(1) Disconnect negative battery cable at battery.

(2) Remove generator drive belt. Refer to 7, Cooling
System for procedure.

(3) Unsnap plastic insulator cap from B+ output
terminal.

(4) Remove B+ terminal mounting nut at rear of
generator. Disconnect terminal from generator.

(5) Disconnect field wire connector at rear of generator
by pushing on connector tab.

(6) Remove generator support bracket nuts and
bolt (Fig. 4) and remove support bracket.

(7) Remove 2 generator mounting bolts (Fig. 5).

(8) Remove generator from vehicle.

It probably has lost all residual magnetic field from the rotor.

You may need to "flash" the field to restore operation.

Search Google for instructions. Sometimes others have found that plugging in an electric drill that does NOT have a throtling trigger and spinning it while connected to the generator will get the generation started again. There are other methods as well.

Take the cover off and flash the rotor again with a 12 volt battery. Positive lead goes to the top or right side brush. Negative to the other brush. Just touch it on, then remove it, and check for power at plugs.
If that doesn't do it, change the AVR (voltage regulator)


If you need further help, I’m available over the phone at https://www.6ya.com/expert/craig_3fa289bf857b1a3c

Since this generator quit working suddenly it's likley that something is wrong with the field circuit inside. The metal surfaces you cleaned off sound like the slip rings of the rotor, there should have been 2 graphite square rods mounted on the plastic bit you took off that ride on these slip rings, they could be worn down or broken.
You'll need a good DMM to measure the resistance between the 2 slip rings (should be about 15 ohms), also measure each of the stator coils (black and white wires in the molex plug) look for an open.
Because the generator has been sitting for a couple of years it probably also hsa lost its residual magnetism, you'll need to flash the field to get it working again once all the parts are confirmed to be OK.