1981 xs400 regulator rewire??

Jasiel Roman

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Hello everyone I have a 1981 Yamaha xs400 and the known good stator and field coil. Problem is when ignition is turned on the field coil doesn't excite even though the brown and green wires going to the connector of the field coil has power and when energized independently the field coil magnetizes. I recently wired in a r292 with both the orange and red lead going to the Brown wire from the harness and the green with green and black with black. I'm pretty sure it's an issue of having my voltage regulator wired in incorrectly. Any help would definitely be appreciated as I've been busting my brain trying to understand what I need to wire properly
 
You may need to positively ground the outer regulator case.

Past that you will need to know if you have a positive or negative controlled field, they did them both ways. Positive type will have one brush to alt grounded, you can check for it.
 
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You may need to positively ground the outer regulator case.

Past that you will need to know if you have a positive or negative controlled field, they did them both ways. Positive type will have one brush to alt grounded, you can check for it.

Thanks for the response amc. Would bolting the regulator to the frame be enough? Or do i have to run a wire to the positive side of the battery? And where would i be able to see if one of the brushes is to the coil is grounded positively? Again i really appreciate your help
 
Regulator bolted to metal frame will work but need the case scraped of paint to ground, or a short separate wire bolted to case and then to frame.

Pull alt cover and check both brush assemblies with positive lead of meter and negative on engine or frame ground point. One brush will show low ohm to zero.
 
Regulator bolted to metal frame will work but need the case scraped of paint to ground, or a short separate wire bolted to case and then to frame.

Pull alt cover and check both brush assemblies with positive lead of meter and negative on engine or frame ground point. One brush will show low ohm to zero.
Do you mean the stator or the field coil?
 
The field coil. Forgive me, thinking of rotating fields with brushes and this one does not have them. Check both ends of filed coil for a grounded condition.

Say how you have the 292 wired to Yamaha harness and be exact.
 
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