Troubleshooting Generator, IH 424

[LAD1DER]

International 424 gasoline powered C-146 engine. Started it up a couple of days ago, and the generator "tellite" is blinking. Obviously not charging because the tractor eventually died when the battery was drained.
Charged the battery, got it started, and put the volt meter on the regulator today, Battery terminal has steady 12v, Generator terminal barely bumps the needle on the meter in time with the blinking light, Field terminal shows no voltage. Checked and tightened the belt, but not changes.
Many questions come up:
1. is field on the ground side, thus not showing anything on the volt meter? If so, how do I test this to see if operating correctly.
2. where does the generator terminal on the regulator get it's power? Does it come from the generator, or is it supplied from another source from the battery? If it comes from the battery and goes to the generator, does it pass through the ignition switch?
3. any ideas on how to trouble shoot it to see if regulator is out, or generator is out?
OK there you have it. I'll be looking forward to the quality suggestions that have helped me fix this thing in the past.

 

[Soundguy]

Your manual will tell you the circuit type, however I'm inclined to think that it is an A circuit system.( other IH units used an a-circuit system ) However so as to ensure not cooking the vr with a fe tests, do the following.

charge the battery

disconnect bat wire to vr, and armature wire to vr. jumper those 2 wires together for a second.. IE.. neither is hooked to the vr.. etc. ( this polarizes an A-circuit genny )


Remove the field wire to the vr.

hook your volt meter to the field wire and ground... now jumper those bat/arm wires again... it's likely you will see power on the volt meter. if so, that is good, and pretty much ensures that it is a-circuit.

Replace the wires to their proper terminal on the vr, except leave the field wire off.

hook volt meter to battery.. static volts should be 12.6 for a well charged 12v'er

start tractor, adjust to 1/3 to 1/2 rpm.. touch that loose field wire from the genny to ground.. volt meter should jump up above 12v.. charge lamp should go off too.

if so, shut down and hook field wire back up to reg.. Restart it and see what you get on the charge lamp and the vom. if it is good, you are set.. if not, post back.

( if you did read power on the field test, then it 99.9% means you have a bad regulator. If you didn't read power, then we need to do a motor test to determin field type again. )

Motor test.

slip belt off genny, disconnect all wires from it.

hook armature to battery.

ground field wire.

if genny spins it is a circuit for sure

if not, jumper arm/bat to field.. if it spins with that it could be b-circuit..

soundguy

 

[zzvyb6]

Don't know the tractor, but you said generator (not alternator).

Some generators are self energizing some are not. It ought to respond with all cables disconnected and +12v applied to the field if externally energized. Use a light bulb to help you diagnose it. Solder some wire to a car tail light bulb with some alligator clips to make life easier (or buy at Radio Shack).

Good candidate for a problem would be brushes are worn or stuck in their seats. "Dithering" it may make it snap to life for a few moments. (Thats a civilized word for hitting it with a hammer).

If you can energize and get 13.5v out of the + terminal, a junction block or ignition swith, or even the idiot light circuit can be a problem. Another one could be the battery terminals are corroded and often act as a diode. Juice in is ok, juice out is not ok, Sand then down, check cable connections and ground continuity.

Use a meter to check the + to - resistace. if its infinite ( no thru circuit) generator is snafu (Brushes or armature).

Alternator, same precautions, no brushes, bad diode(s): either shorted (passing AC) or open (no current). Check battery water level. A diode issue usually causes water to boil off very quickly if you are sending AC to it.

In all my years, its seldom been a generator or alternator problem (brushes once) its always be a connection problem. Connection problems have low cost fixes but can happen very often. The connections list should include a loose battery post (not the terminal lug, the post in the battery).

Hope this helps. At least it will get you thinkin.

 

[Soundguy]

ZZVYB6 .. I'd be carefully about giving people advice about powering the field on a genny without actually knowing what circuit type it is. If that genny is indeed an A-Circuit unit, like many other IH gennies, then the moment he hits it with power to the field terminal, then his 40$ regulator goes up in smoke.. as the field contacts are grounding types, and are default closed when it is not running. The Self energizing gennies you speak of are generally the 3rd brush variety, and utilize cutouts ... though there are certaintly examples of 3rd brush gennies using regulators a couple different ways depending on whether the field terminal is available.. or if it is just using the cutout in the relay.

My message gave him good -safe- directions on how to determine circuit type without smoking anything. It also shows him a motoring test which will check the brushes, and field coils, and the comutator and mica. Also shows a safe way to polarize without smoking anything expensive.

soundguy

 

[LAD1DER]

OK Soundguy, I did get voltage on the field wire when I hit the battery / armature wires together.

Upon re-attaching the batt and arm wires and starting the engine, I did not get any spike in voltage when I grounded the field wire and the charge lamp remained lit.

So am I reading it right that you suspect a bum regulator? I didn't proceed with the motor test as I wasn't sure if I'd reached a conclusion yet.

Thanks,

 

[LAD1DER]

Dropped the regulator off at an automotive electrical repair shop. Guy had just rebuilt a generator for a '55 Chev. He put the rebuilt generator on the tester with my regulator. My regulator was stuck in WFO mode. Got a new one on order $32.00, be here next day.

 

[Soundguy]

Let me know how it turns out.

I'd try the motor test while you wait.. if the old reg was stuck on hi charge. the genny may actually be toasty and already have flung it's solder.

soundguy

 

[LAD1DER]

OK, before putting on new regulator, I did motor test. The generator took off spinning when ARM + and FLD -.
Put on new VR, jumped the BATT and ARM to polarize the gen., started the engine, and alas, no change. The light is still on/blinking. I hooked the volt meter to the battery, took the FLD wire off of the VR, then grounded the FLD on the gen. and no change on the volt meter.
What's next?

 

[Soundguy]

Try this.. polarize again, IE.. jump bat and arm with a jumper wire.

Start tractor, disconnect field from genny, ground field to genny case.. now jump at and arm... charge lamp go off? if so.. bad regulator.

On the bottom of your regulator, there should be a bias resitor between ground and field... if not.. you have the wrong regulator...

this test needs to be done at 2/3 throttle.. gennies are not very effieient at low speed.

most gennies that motor will charge.. most gennies that charge will motor.

soundguy

 

[tree farmer]

After I had the generator bench tested a few years ago, I replaced the voltage regulator on my IH 3414 ( industrial model of the B 414) . The idiot light still stayed on, but seemed to charge the battery to some degree. Later, it quit charging completely. I found the fan belt was so old and brittle that it couldn't get a good grip on the pulleys. Replacing the belt solved the problem, but if your IH is like mine, have fun, as the fan belt is tensioned by loosening a set screw on the drive pulley and twisting the halves of the pulley together, making it a larger diameter in the center. Also, a good tap on the regulator cover with a screwdriver handle seems to be needed from time to time. This tractor gets used only about 10-20 hours a year any more, so I think our coastal air causes corrosion to form between the contacts in the regulator. Hope you get it fixed. These old IH's just go forever. .....Dan.