Setting generator third brush

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Clockdoc
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Setting generator third brush

Post by Clockdoc » Sat Jul 20, 2019 5:23 pm

I just rebuilt my generator and was wondering when I set the third brush do I hook the ammeter wire directly to the output post bypassing my fun projects regulator?

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TRDxB2
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Re: Setting generator third brush

Post by TRDxB2 » Sat Jul 20, 2019 6:06 pm

Good question - based on the Fun Projects VR instructions at www.funprojects.com/pdf/10505R6-041418.pdf Based on the instructions I would say that the procedure is to adjust the Voltage Regulator's output by adjusting the third brush. "Connect the battery wire (car wiring) to the output (Battery) terminal of the regulator. You may notice a momentary "spark" when the battery wire is first connected to the Battery terminal.The Ammetershould not show any charge or discharge after the battery wire is connected. ......... Do not remove the voltage regulator cover as there are no user serviceable parts or adjustments inside the voltage regulator. Never allow a modern generator shop to have your VR - remove it.
Setting the generator third brush A) Loosen the generator dust cover bolt and lift off the dust cover. etc"


Scott_Conger
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Re: Setting generator third brush

Post by Scott_Conger » Sat Jul 20, 2019 7:23 pm

These are the FP instructions for setting 3rd brush on a Model T: http://www.funprojects.com/pdf/5055R6-041418.pdf
Additionally, you should start with the brush all the way CCW as viewed from the front of the car (away from the engine). This way you will be increasing the output rather than risking full-tilt-boggie output and possibly injure the VR.

Personally, I would set the generator with a good known cut-out first and save the VR from abuse that it may receive from a rebuilt generator at an unknown output.

The adjusting instructions I've referenced are Model T specific, and are somewhat different than the instructions for a Model A.
Scott Conger

Full Flow Float Valves - deliver fuel like Henry intended!

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TRDxB2
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Re: Setting generator third brush

Post by TRDxB2 » Sat Jul 20, 2019 8:58 pm

Good point Scott - when he time comes I'll adjust with the cut-out and when things check out replace it with the VR

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John.Zibell
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Re: Setting generator third brush

Post by John.Zibell » Sat Jul 20, 2019 10:17 pm

This is the Model T instruction.

Note: If you have a 26/27 reproduction ammeter it is not accurate enough to perform this procedure. You can place an older style or other more accurate ammeter in line between the VR and harness battery wire to make the third brush adjustment.
Voltage regulator.pdf
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1926 Tudor

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