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Voltage Regulator / Rectifier Question on 520H

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I need to replace the voltage rectifier on a 520H. 

So I ordered the following replacement part: "New Rectifier Regulator for Onan P-Series Alternators 16 17 18 19 20HP Engines 20 Amp Rating 191-1748, 191-2106, 191-2208, 191-2227 by Crank-n-Charge"


This new rectifier has 3 male spade connectors, yet on the tractor I have voltage rectifier with 4 spade connectors.  I've attached a picture of the current rectifier.


Can I use this new rectifier and assume I can wire the white and grey wires together?


Or is this currently installed rectifier something special since it has 4 spade connectors and the two wires need to be independent of each other?


Thank you for helping me out.




520H Voltage Rectifier.jpg

Edited by kwalshy
error on wire color, changed from white to grey

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there are only 3 on the Rectifier as one is piggy backed on the same connector

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2 white wires are the stator wires they should connect to the 2 outside connectors. The red is going to the fuse block to the 30 amp fuse, then back to the battery for charging. The grey wire is piggy backed and is your tachometer wire, it is that way from the factory and just clips on the way you've got it. Looks like you are all set.

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Yes, I replaced mine on my worker '88 520H last December and added a second wire on the double terminal to the tach. I then had a working charging system and a working tachometer.  Some previous owner had messed with the wiring 9 pin connector, so I ran a direct wire to the tach from the regulator.

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Thank you all for the feedback.  I appreciate the help!  

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