QuestionQUESTION: I have a 1957 Massy-Harris-Ferguson farm tractor that has a 12 volt generator and a voltage regulator just like any car up to the early sixties. My problem is the generator was blown out when I got it (winding wires sticking out of the sides) so I had it rebuilt and put on a new regulator, polarized the regulator according to the instructions that came with it, but it won't charge. help!
ANSWER: Of course I have no reference material on this set-up, and so I don't know if they used the Ford system or the one used by all other manufacturers, so I cannot even advise you as to how to troubleshoot it.
If you don't have a wiring diagram or a shop manual for the tractor, my advice is to get yourself one! I have both an old Massey Ferguson skip loader and an old John Deere Dozer, and I was able to buy new shop manuals for each of them from the relevant tractor parts dealer out here in CA - so I assume you can do the same by searching for tractor parts suppliers on the internet.
In general, assuming the generator was properly rebuilt, and assuming it is being turned by the engine, there should not be any problem other than the correct connection of the various wires, but without the diagram to follow, I can't tell you much more.
Make sure that the generator itself and the voltage regulator is securely grounded to the tractor frame, and that the ammeter or voltmeter, whichever it has, is working and hooked up right.
Look at the labels on the terminals of the regulator and generator, and make sure that you have the wires connected between the right terminals. "A" means the armature of the generator - the largest terminal on it if there are two sizes. "F" means the field terminal of the generator - the smaller of the terminals. "G", if it has one, is the ground connection, which is obvious because it goes right into the metal case.
On the regulator, there should be an "A" (some have "G" there), and a "B"- which goes to the battery, or ammeter, or voltmeter, depending on
what your machine has, and an "F". There may also be a ground wire, or it may depend simply on the physical mounting screws for grounding.
If you have electrical testing equipment, and if you describe to me in detail what the regulator looks like (size, number and type of connections) and any numbers on the generator, I might be able to give you some step by step troubleshooting advice, if I am familiar with your system.
Post another question to me if you have a VOM (Volt-Ohm-Meter) and can answer those questions.
Dick
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QUESTION: The generator has two terminals, one marked "A" the other marked "F". The regulator has four, "F", "BAT", "L", and "GEN". The generator terminal marked "A" goes to the "GEN" terminal on the regulator, the "F" terminal goes to the "F" terminal on the regulator, the "BAT" terminal on the regulator goes to the battery side of the starter solenoid, through the ammeter, and the ignition switch,and the "L" on the regulator goes to the starter button. I do have a VOM.
AnswerI apologize for being slow to answer - the allexperts system is having some kind of a problem - I got no questions for a few days, now there are a bunch of them stacked up in my in-box!
I need to know the type of connections on the regulator - are they screw terminals or is it a plug in - connector with all 4 wires in one plug?
This is important to know, because the troubleshooting procedure is totally different for each type.
I'm going to assume that it has individual screw type terminals - but if that is the wrong guess, get back to me and do NOT do the following!
With the engine running at a fast idle, put your voltmeter on the "A" terminal on the generator, and then with a separate wire, ground the "F" terminal on the generator to a known good ground - like the case of the generator itself. The voltage on the generator "A" terminal should jump up to way over 12 volts - at least 14 and maybe higher. If it does, your generator is OK. Don't keep it on there more than a minute or so, as you are calling for MAX output from the generator.
Now, move your meter and your grounding wire to the same terminals on the regulator, and repeat the test. If you get the same result, you've proven that those two wires are OK.
Now, move your voltmeter to the "B" terminal on the regulator, and repeat the test again. If you still get the 14 volts or so, everything seems to be OK, are you sure the battery isn't being charged? How are you determining that the battery isn't being charged.
If you DON'T get the 14 volts or so at the "B" terminal, your regulator isn't working, either because it isn't properly grounded, or because it is defective.
I'd appreciate knowing what you test results are.
Dick
