Voltage regulator

[cubcadetguy123]

Hey guys, I am need a little help regarding voltage regulators. Have any of you ever had to Re polarize a unit? thanks

[ol'George]

A voltage regulator usually only needs polarized when installed new the first time to "train" the current flow direction.
If you have a charging problem most generally you have issues other than polarization.

[cubcadetguy123]

what issues would you be talking about? Wiring or generator problems?

[ol'George]

It could be any or all.
First what is the problem? and what are you working on?
There are test procedures for various problems
What have you done to test if there is a problem, the more info, the more helpful.

[cubcadetguy123]

I am working on a 1970 cub cadet 73 model. The tractor will start and run but after 4 or 5 starts the battery will start to sound weak. My dad says that he remembers having to Re polarize voltage regulators after they sat for long periods of time.

[Yosemite Sam]

Polarizing a voltage regulator.

It has been said that the S/G on a Cub Cadet Polarizes itself each and every time one turns the key to start the tractor. Not everyone agrees that this is the case so here is a starting point if you are experiencing a "no charge" situation.

With ALL the wires on the S/G and the V/R connected AS THEY SHOULD BE, briefly connect the generator armature to the battery hot terminal. In most cases the easiest way to do this is, using a short jumper wire, touch one end to the Batt and the other end to the Gen terminals on your V/R. As soon as contact has been made you should see a spark and the process is finished.

Chances are that didn't do what you wanted it to so here is the next thing that you need to do to get to the root of your problem.

There are about as many ways to check a S/G as there are people here, this is how I do it so there is absolutely no doubt in my mind if there is a problem with a S/G or not.

You need a 1/2 " wrench and a jumper wire (about 12").

Loosen the bolts on the S/G and take the belt of the pulley, turn the key to the start position so that the S/G spins and hold it there. Using your jumper wire, attach one end to the "A" terminal on the S/G and the other end to a known good ground.

Once the "A" terminal is grounded, the S/G should begin to slow down (a considerable amount).

If the S/G does not slow down during this test it is defective and should be repaired. If the S/G does slow down during the test, we can move on to the next step.

Other folks will tell you different ways of performing this same test, providing they know what they're talking about, this way or other ways are not necessarily wrong, they are just different.

See what this test yields and let us know.

[ol'George]

Before trying that Generator function test you can check Voltage @ the battery terminals before starting, it should be over 12 V. approx. depending on battery charge.
Then @ wide open governed rpm---3600 approx,
You should get a little over 14V. approx if the system is performing properly.

12.6 volts tested after a battery has rested 24 hours (neither charged or discharged) is considered fully charged.
That said I have seen less and they worked ok as older batteries sometimes will not come up to that voltage, but close.
You might be experiencing an older battery condition and not sufficient time to recharge between starts.

Does it eventually not start and needs to be put on a charger or just seems to turn over slower after multiple starts?
---Are we jumping the gun and it works ok but you just wanted a polarizing question answered?

[cubcadetguy123]

Thanks for the tips. It all seems to be working fine now. I'm going to take it as it needed worked a little bit. She's going to a show tomorrow and if all is well after that I can chalk this up to a successes.

[save_old_iron]

Originally Posted by Yosemite Sam

Polarizing a voltage regulator.

It has been said that the S/G on a Cub Cadet Polarizes itself each and every time one turns the key ...................

briefly connect the generator armature to the battery hot terminal. In most cases the easiest way to do this is, using a short jumper wire, touch one end to the Batt and the other end to the Gen terminals on your V/R. As soon as contact has been made you should see a spark and the process is finished.

Correct me if I have misread this, but doesn't the gen armature get connected to the battery + terminal EVERY TIME YOU TURN THE IGNITION SWITCH TO START? A schematic for the charging / starting system suggests it has to.

The only thing that can change the polarity of the output in this style gen is to change the DIRECTION the wires are wound in the field coil.

[Yosemite Sam]

I agree, but there are those who don't, maybe they have had different experiences.