Generator or Regulator Failure?

[rdockery_3]

My 2011 RV12 dropped to 12.3 volts or so during flight so I turned everything off that I could and flew back to my home base which was only about 15 minutes behind me. I'm hoping it's the voltage regulator. I have the silent hektik 4120 regulator on mine. Is there a way to test the regulator to know for sure which one it is?

I have read of people using the John Deere regulator on the RV12. Will it fit the same place the SH 4120 does?

 

[akschu]

Disclaimer, I'm not a rotax guy, just trying to help, but could be wrong:

With the engine running, you should be able to take a meter in AC mode and probe the two orange leads on the left side and see if the alternator is giving anything to the regulator.

The internets say that the rotax permanent magnet setup is very reliable and it's usually the regulator that fails, and this one is known to fail. Also, the folks at B&C make a pin for pin replacement: https://bandc.com/product/avc1-advanced-voltage-controller-14v-homebuilt/#installation-kit

If those things are indeed true, I'd consider upgrading just to avoid being stranded.

 

[Piper J3]

Yes, the JD will fit where you have SH mounted. I have John Deere VR mounted to a thick aluminum sub-plate for improved heat disipation. I also use thermal compound paste on the base of the voltage regulator. In addition, the sub-plate is mounted on standoffs so air can circulate underneath.

 

[rdockery_3]

Yes, the JD will fit where you have SH mounted. I have John Deere VR mounted to a thick aluminum sub-plate for improved heat disipation. I also use thermal compound paste on the base of the voltage regulator. In addition, the sub-plate is mounted on standoffs so air can circulate underneath.

Mine has six wires connected to it. Will the John Deere still work, And which wires would I not connect? Also, are the dimensions the exact same or will I have to drill new holes in the firewall?