Alright so the Alternator that came with my RB25 was bad, unfortunately I hadn't noticed this under the 30day Warranty period on it so I'm shit out of luck. RB25 Alt's go from $150-$200, so immediately I said "fuck that" and went searching for a Nissan Alt that was similar. To my surprise a KA one isn't far off and you can get them at yards for $15 and EVEN BETTER, the RB Alt face BOLTS right onto the KA Alt (I'll show you both options below. Definitely more in my budget and here's how I made it work...
Comparison: Top two are s14/s13 KA Alts, Bottom one is RB25 Alt. They all have same Diameter Pulley. Rb25 is 80amps, Early KA are 80amps, and 95+ KA I believe are 90amps. So your fine with either one you pick.
This is how far off the RB25 bolt holes are from the KA one..
Here's the RB25 Face bolted on a KA body. If you do it this way, all you have to do is weld a small peice on the back flange and drill a hole and your done..
But if your like me and want to rebuild your RB25 alt and make some money, heres the way to do it and only use the KA alt. Drilled some holes..
Pressed out the Metal sleeve in the Back flange..
And filed the holes out wider..
Try to make the filed hole the same diameter as the bolt so it doesn't move around when installed and running.
Top and Bottom filed out..
Difference between RB25 and KA alt face width, you see KA one is thicker...
So you will need the KA Bolt (showing comparison between RB25 Bolt and KA)..
Now for the wiring, the plugs are exactly the same but the KA one has a thicker wire, so I rewired it all with a thicker wire using the KA Plug. As for the white/red wire comming out of the plug. Either wire it into your dash light for the alt, or (like I did) Go Alt->White/Red->light (any light works)->12v power. THIS WIRE MUST BE HOOKED UP OR IT WILL NOT WORK!!!..
Once done, your RB25 ground and power bolt right up, along with your RB25 Alt Belt. And your done!
Comparison: Top two are s14/s13 KA Alts, Bottom one is RB25 Alt. They all have same Diameter Pulley. Rb25 is 80amps, Early KA are 80amps, and 95+ KA I believe are 90amps. So your fine with either one you pick.
This is how far off the RB25 bolt holes are from the KA one..
Here's the RB25 Face bolted on a KA body. If you do it this way, all you have to do is weld a small peice on the back flange and drill a hole and your done..
But if your like me and want to rebuild your RB25 alt and make some money, heres the way to do it and only use the KA alt. Drilled some holes..
Pressed out the Metal sleeve in the Back flange..
And filed the holes out wider..
Try to make the filed hole the same diameter as the bolt so it doesn't move around when installed and running.
Top and Bottom filed out..
Difference between RB25 and KA alt face width, you see KA one is thicker...
So you will need the KA Bolt (showing comparison between RB25 Bolt and KA)..
Now for the wiring, the plugs are exactly the same but the KA one has a thicker wire, so I rewired it all with a thicker wire using the KA Plug. As for the white/red wire comming out of the plug. Either wire it into your dash light for the alt, or (like I did) Go Alt->White/Red->light (any light works)->12v power. THIS WIRE MUST BE HOOKED UP OR IT WILL NOT WORK!!!..
Once done, your RB25 ground and power bolt right up, along with your RB25 Alt Belt. And your done!
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