FORD 4000 Not Charging

[number two]

A friends Ford 1966 4000(actually a 4101 model) has the charging system warning lamp on and a voltage check at the battery shows 12.5 volts at 1500 RPM-obviously not charging. I'm hoping someone could help me with troubleshooting suggestions. It's been just too long since I've worked with a generator and regulator system,and can't even remember how to polarize the system.
I've got the I&T service manual with the starting/chaging system wiring diagram,but no instructions.I have the usual tools-DVOM,test light,load tester,Power Probe. Just lacking a direction. Any advice appreciated as always.

 

[dqdave1]

Check voltage regulator; it may be the culprit.

 

[TedLaRue]

I'm supporting dqdave1's suggestion.

The voltage regulator on your tractor is almost certainly mechanical unless they made a solid-state replacement and someone installed that in recent years.

Find your regulator by looking in that service manual, or by tracing the wire (probably moderatly heavy gauge) from the generator toward the battery.

Those regulators worked kind of like a normally-closed relay. The voltage from the generator was applied to the coil in the relay. When the voltage got too high, the relay clicked shut, opening the circuit which charges the battery.

I vaguely remember bending contacts in those regulators to adjust them, but it sounds like your regulator has failed completely (i.e., the relay is always open, so no charging current reaches the battery).

If you're adventurous, you might take advantage of the fact that this thing is mechanical and you can see how it works. Open it up (probably has a metal cover and you can pry up the tabs) and check for a broken lead to a coil. There's nothing quite as satisfying as taking the long chance to fix something and then succeeding. Well, almost nothing.

 

[CCWKen]

I agree the prime suspect is the regulator but you can eliminate the generator as the problem and check the regulator with a quick test.

There should be an "F" terminal on the generator and the regulator. This is the Field winding connection. The field winding controls how much current the generator is to output to the BAT terminal. In simple terms, the regulator applies voltage to the field to produce current at the BAT terminal.

Attach a volt meter on the battery terminals. Get a 5-10W ~1-2 ohm resister. (An ignition resistor is ideal and available at most auto parts or Radio Shack) Attach the resistor in series with a piece of 14ga. wire. Attach one end of the wire to the + post of the battery (- post if positive ground system) and with the engine running, touch the other end to the Field terminal on the generator. If you don't see an increase at the battery, the generator is bad.

Otherwise, check for loose connections on the Field wire from the gen to VR and/or the "I" wire from keyswitch (or starter I post) to the VR. With the key on, you should have voltage at the "I" terminal of the regulator. If you have battery voltage at the I terminal an nothing or low (< than ~8v) on the F terminal, replace the regulator.

Don't try to bypas the regulator by leaving the test wire connected to the Field terminal. You can boil a battery is short order.

 

[Soundguy]

Attach a volt meter on the battery terminals. Get a 5-10W ~1-2 ohm resister. (An ignition resistor is ideal and available at most auto parts or Radio Shack) Attach the resistor in series with a piece of 14ga. wire. Attach one end of the wire to the + post of the battery (- post if positive ground system) and with the engine running, touch the other end to the Field terminal on the generator. If you don't see an increase at the battery, the generator is bad. .

I'm sorry.. but that is just plain bad / incorrect advice. there are at least 3 other problems other than 'generator is bad' that your test completely overlooks.

soundguy

 

[Soundguy]

A friends Ford 1966 4000(actually a 4101 model) has the charging system warning lamp on and a voltage check at the battery shows 12.5 volts at 1500 RPM-obviously not charging. I'm hoping someone could help me with troubleshooting suggestions. It's been just too long since I've worked with a generator and regulator system,and can't even remember how to polarize the system.
I've got the I&T service manual with the starting/chaging system wiring diagram,but no instructions.I have the usual tools-DVOM,test light,load tester,Power Probe. Just lacking a direction. Any advice appreciated as always.

Ok.. that is a 12v, negative ground, B-circuit generator and regulator system, that uses a lucas generator and regulator.

here are a couple tests to do to check out components:

First.. polarize the system... jumper bat to field for a couple seconds.

Motor test: slip the belt off the genny, jump bat to armature, and bat to field.. genny should spin.. most gennies that motor will charge.. most gennies that charge, will motor.

Next, slip belt back on, put volt meter on battery.. start tractor, get to 1000rpm.. if charge lamp don't go out / volt meter don't come up, jumper bat to field... if still nothing, then jumper bat to arm as well.. if charge comes up, regualtor is bad.

new regulator is available at CNH dealer... I just put one on my 5000.. ( same regulator / genny ).. has a couple keyed connectors on it.. so it's ahrd to plug up wrong.

If it does turn out to be the genny, they usually don't cost much mor ethan about 80$ to fully rebuild.. and not much more to get a replacement.. my local store has the 'will-fit' repalcements for 89$ plus core swap. Field connector is a couple inches over.. but it all mates up.. just swap over your tach drive and go..

soundguy

 

[Egon]

If its Lucas stuff just change it out and save some headaches.

 

[Eagleview]

Get a 1 wire alternator off a car and fix it forever .

 

[number two]

Gentlemen,thank you for all the replies.You've helped me a great deal getting up to speed on these older systems.Extra thanks to Soundguy for the troubleshooting sequence and polarizing info.Naturally I suspect the regulator but I just hate changing parts without diagnosis first. Back when I was driving generator stuff,I wasn't that good a tech and was a parts changer.I will be over there to perform the tests in the next week and if you like,I'll post back. May even have more questions. An additional thought,after the yet to be determined repair,I believe I will need to polarize again before hooking up the battery cable?Thank again.

 

[number two]

Oh yeah Egon,I've always remembered those Lucas "Father of Darkness" tales. And Iron Horse,this guy isn't going to want an alternator conversion,but it makes good sense to me.In the old days,I believe the Delco 27SI was the popular conversion alternator? Many tanks again.