View Full Version : OT - Wiring in Nippon Denso Alternator in place of existing Prestolite model

11-06-2012, 11:54 PM
You fellas rarely let anyone down with problems such as these

The boat I work on has 2 Kohler/John Deere 125kW generators powererd by powertech 8.1 litre prime movers; one of the on-engine alternators sounds ropey so I dragged out the spare from storage and it is not a drop in replacement.

The existing is a Prestolite 8MR3404G with a 8RG3063 voltage regulator attached and the one from storage is a Nipon Denso RE65414 (102211-0400), which has a moulded plug with 2 wires coming out of it and 3 terminals when the plug is removed. The existing wires will need the terminal ends changing but I would like some assistance as to which wire goes to which terminal. There appears to be a pos, neg and one attached to the voltage regulator

I have also asked this question on the Prestolite support forum but it doesn't seem to move very fast. I do have some pics but my photobucket account is lost to the sands of time.

Thanks for any help

11-07-2012, 11:37 AM
Here are the diagrams that I have.



The sense connection is used to adjust the voltage output to compensate for losses in the wiring. You can run that wire to a point in the harness where you want to maintain 14.2 volts. The alternator will read this point and adjust it's voltage. I don't think it has to be connected. The alternator will just maintain 14.2 at its Batt terminal.

I have a small unit on my T bucket and it works great.


11-07-2012, 10:58 PM

Attached link shows the wiring diagrams for 3 different types of NipponDenso alternator plugs: http://westfield-world.com/daihatsu_alternator.html

11-09-2012, 09:07 PM
Thank you very much for your help with this, I now have it sorted!