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I've followed Ricky Racer's recent generator thread and it has prompted me to evaluate my 6 volt charging system, generator with voltage regulator/cut out combination. As I go through the flow chart all indications are that the voltage regulator/cut out is bad. However, when I remove the voltage regulator/cut out from the tractor and test it, it appears to be fine. I've traced back all of the wiring and grounds, repolarized the generator.
My question is: can a defective voltage regulator/cut out appear to test fine on the bench and then not work correctly when installed on the tractor?
its cant be a voltage reg and a cut out. It is either a voltage regulator or a cut out. If you have 4 position light switch then it is probably a cut out if it hasnt been replaced. L is low rate of charge, H is high rate of charge. If its a 3 positon light switch then it has a voltage regulator. The most common problem with voltage regulators are that the contact points get corroded. It is a easy fix. Using a point file you file the grunge build up off the contacts. First remember to disconnect the battery before filing. wipe contacts with a rag.
Collector of Farmall cubs and cub cadets.Injoy helping people keep their cubs running. Years of experipnce.
Three position switch. I guess you'd call it a voltage regulator.
I'm sorry, the manual describes 2 elements inside of the box, a cut-out switch and also a current/voltage regulator.
With the tractor running there is no charge indicated on the ammeter. With the F terminal of the generator connected to the battery ground I get a normal charge on the ammeter.
The voltage regulator appears to test fine on the bench, but when I connect it in the tractor nothing. I've checked all of the grounds, determined that all of the wires are correct per the wiring diagram.
I cleaned the voltage regulator contacts as recommended by Jim Becker. They did not appear to be dirty. I'll check the air gap. I may just buy a new voltage regulator and find out what happens.
The box refered to as a "regulator" has a cut out inside, the box refered to as a "cut out" does not have a regulator inside.
Leaving off the "/cut out" when talking about a regulator makes it less confusing since all regulators have one even though it is technically correct.
Sounds like a bad regulator if the wiring is good. How did you bench test the regulator/cutout?
Correct, Delco "voltage regulators" have a cutout inside, this is what disconnects the battery from the generator when parked.
I've been going thru a similar process with my SA, which uses the same regulator as the Cub. My original one is intermittent and the points are pretty far gone, sometime in it's life it got hot enough to melt the plastic that holds the lower contact of the points and has eroded the contacts. When it works, the charging current is only 1 Amp. So I decided to buy a new one and ordered one from a prominent vintage tractor house and put it on, didn't work out of the box. I took the cover off to look inside and the workmanship is very bad. The cutout points don't meet right, the upper contact holder was bend at about 45 degree angle down so when the points tried to meet they were just touching by a hair instead of the full surface of both contacts; cold solder joints too. Made in China, $32.95 wasted. I don't think these regulators are being engineered, just copied from the old ones and looks like a lack of skill in factory adjusting them to work properly. I guess if you can afford to use them like fuses, you'll find one that works.
So I ordered one thru Autozone, VR646 that crossed to the original Delco number 1118308, costs about 2x the other one, don't know where it's made but at least from a name company. And Autozone says if it doesn't work, bring it back for a full refund, no questions asked.
I rebuilt my generator and it bench tests good also except for the second part of the motor test. On the running tractor if I ground the F terminal I get a charge of about 8 Amps. With discharge of 3 1/2 Amps for the coil, that means the generator is supplying 11 1/2 Amps, which I think is reasonable.
On the bench test, I posted the question about the second part of the field test and got this answer. I'm going to repeat the motor test on the tractor using the battery, it might be the battery charger I used can't supply enough current for the second part of the test.
I did a motor test on my generator using the battery and it spins when "F" is grounded and battery connected to "A". When I lift the ground off the "F" it continues to spin, not faster, but slower.
I installed the regulator from Autozone and it the system is charging. Good news, the regulator is stamped "Made in USA".
To test the system, I used a tester made by Allen Co. probably 50s or 60s vintage that I found a tractor show last weekend in Fredericksburg. I had to replace a few wires that had become brittle but it works great, especially made for testing generator/regulator systems. It has 4 leads, two for connecting in series with the batt lead to measure current and two to measure the regulator voltage. And the regulator test scale has a a green zone to tell you immediately if the regulation is in spec.
TJG; Try this link, it may be use full to you.
If it works on the bench it should work on the tractor, with the possible exception of not enough voltage available to activate it.
Mark "birddog" Birdeau
Thanks BirdDog. That is the post I used to bench test my voltage regulator. It is an excellent post.
Today I purchased and placed a new voltage regulator and now the charging system appears to be correct and functional.
I just couldn't figure out why the voltage regulator appeared to work on the bench but not on the tractor.
My experience with Autozone has been exactly that. I have returned several coils under warranty and they have never questioned it - Only concern they have ever expressed is whether they have it in stock. And they don't care whether you purchased it at that particular store (once I had to go to a different store because it was out of stock where I purchased it).
Eddie - a 1959 International Lo-Boy named after my father in law, who who bought her new.
Todd; Remember, that test really doesn't tell whether the regulator is fully functional, only that the cut out part is working. (I forgot that when I said in my previous post, that if it worked on the bench it should work on the tractor)
To find out more it would have to tested on the tractor while running like in my charging post. I realize that if you found my post on the regulator test you probably found these also. But here they are just in case. Also a mute point seeing that you already replaced it, but maybe you want to play with it some more.
Mark "birddog" Birdeau
I've been having VR problems also. Followed flow chart and my VR was bad. Bought new one from C&G. Well guess what, bad out of the box. Went to Advance Auto, Auto Zone, O'Reilly's, and Napa. All complete idiots, had no clue. I read this thread and called Auto Zone with part number in hand. Well guess what, I've got to pay for it before they will order it. I remember now why I quit doing business with Auto Zone
So, what can I do with one of these "Made in China" voltage regulators? I have a Farmall Super C tractor with regulator problems too. Initially my wiring system was eaten up by the mice in the barn, and burned out the original voltage regulator. So I bought one from the CASE/IH dealer and it was one of the "China" ones and didn't work for very long. So I bought another one at Tractor Supply. Looked the same. It didn't work very long either. Looks just like the one on my Cub LoBoy. Or should I just go buy a American Made one from Autozone? And if they order one for me what will guarantee that it is American Made?
1959 International Cub Lo-Boy W/Fast hitch, 59 Woods, dozer blade, plow
1954 Farmall Super C W/Fast hitch, belly dozer blade
1950 Farmall M
I don't know. Some work, some don't. I bought a Chinese one, didn't work out of the box.
Since you say a few have lasted awhile, maybe you have another problem that's causing them to fail.
The one I got from Autozone works, time will tell for how long, but it's American made.
If you order one, and don't want it, they'll refund your money even if you install it. (that's what they told me).
Thomas, either way you do it you have to pay. Paying for special orders upfront is common, there was no shipping charges applied. Before you pay, ask about their return policy, I did and they said they'll refund the money even if you install it. I'm not advocating Autozone, but I didn't have any problem with my order, got it in 2 days.
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