Generator cutout

D

Dkrahn

Member
Hello everyone. I run my A and I get no amps on the meter. I turn on the lights and immediately goes to discharge. Never goes to the charging side. I check volts on the input side of the cutout. It shows 1.8-2.0 volts. One of the possible fixes is the ammeter. So I replace it, same thing.. One of the other choices is the generator cutout. I pulled it off and opened it up, all looks good in there. Is there a test? or do we feel VERY confident that is the culprit?


I did open up the generator and those brushes look good. Not quite understanding the instructions in Les's book on how to get more voltage.


Appreciate all help
Dean
 
Apply power to the generator and see if it motors.

Check voltage at the output terminal.

Since its been apart try polarizing it.
 
With the cover off the cutout and engine at fast idle. see if the cutout points are closed. If so run a points file between the points after shutting the engine down. Try once again and see if there is a charge.
 
Only 2V output indicates a faulty generator. May be bad connection but more likely I think burned field windings. I doubt it will motor.
 
Be the same as when the points stick closed. The generator would try to motor and
you would get some sparks between the points and file. you could just disconnect the battery wire at the cutout.
 
Apply power to the generator and see if it motors. Engine starts and runs, only issue is I am showing discharge of 10amps when I turn on the lights..Normal running is showing 0 amps

Check voltage at the output terminal. less than 2V at output

Since its been apart try polarizing it. Not sure how to do that..
 
Dkrahn said:
Apply power to the generator and see if it motors. Engine starts and runs, only issue is I am showing discharge of 10amps when I turn on the lights..Normal running is showing 0 amps

Check voltage at the output terminal. less than 2V at output

Since its been apart try polarizing it. Not sure how to do that..
Click to expand...

You're running on battery only. 0 amps where the coil is connected to the battery side of the meter, battery supplying 10 amps to the lights.

Cutout won't close with only 2 V, generator won't recharge battery.

Polarize with a jumper across the cutout to apply battery to the gen output post for about 1/2 second. Expect sparks.
 
So Badpuppy, you are saying jumper across, from one side of cutout to the other? Just to also confirm, there is wire from the breaker box (box on firewall) and lights, on the one side of cutout and nothing on the other side of the cutout.
 
Should look something like this.
 

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1. Remove fan belt.

2. Remove the wire from cutout that goes to the terminal box on the firewall. Do not let it touch any grounded point. This wire should be hot (connected to battery). If in doubt use a bulb or volt meter to verify.

3. Touch the wire that was removed from cutout to the opposite side, the output terminal of the generator. The generator should turn as a motor. If not, the generator is defective.

4. If generator is defective from above test, take it so someone to have it rebuilt or buy a rebuilt generator from one of the vendors on an exchange basis. Follow the vendor's instructions as to what parts to remove from the generator before shipping.
 
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This may be obvious, but when you check the voltage output, make sure the engine rpms are above 600 or so. Testing voltage at "normal" idle will always give a low reading.
 
GREAT test and helpful... The Generator does spin up / rotates fine. So I wont worry about the generator. Thank you
 
Dkrahn, Good news that the generator motors.

The amount of generator voltage is controlled by a third brush in the generator.

1. Put the fan belt back on and hook up the wires like they were before. Adjust the fan belt for about 1/2 inch movement.

2. Take the band off the end of the generator.

3. There are 3 brushes, only one is moveable. The center brush is the moveable one. Push the moveable brush down to about half its travel.

4. Start the engine and run at a fast idle. Check the ammeter to see if you are charging. If not, stop the engine and push the moveable brush down a little more. Start the engine again and run at a fast idle and check the ammeter. Repeat this until you are charging about 10 amps. A fast idle is 1,200 rpm, about twice what the engine normally idles at.

5. If you push the moveable brush all the way down and you are still not charging at a fast idle then you may need a new cutout or the generator is weak.

6. To check to see if the generator is weak, run at a fast idle and check the voltage at the generator terminal, opposite from where the wires are connected on the cutout. You should be getting more than 7 volts. If it is only 1.8 to 2.0 volts as you reported earlier then you will need to have the generator rebuilt. If it is 7 volts or higher then it is the cutout.
 
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