Van's Air Force

The definitive Van's Aircraft support community! Buying, building or flying an RV? Join our exclusive family of mentors and enthusiasts!

PSA: Rotax B-Regulator Connector Mount

Tony Kirk

Well Known Member
Patron
I've seen a couple RV-12iS installations that have the newer Amphenol Round connector on the B-Gen Voltage Regulator that didn't have the VR connector mounting bracket installed.

Rotax addressed the connector mounting bracket installation (951981 $61!) in the Service Instruction SI-912 i-024. It's installation is not covered in the KAI. The bracket was included in my engine kit with the Rotax fusebox. It's not a Van's part!

I figure if Rotax is going to include a $61 bracket to hold the $585 connector it should probably be installed.

I didn't like the way the connector fit in our installation using the instructions in the SI, so I mounted mine to the B-Regulator ground stud. This keeps it out of the way of the cooling air scoop on the top cowl, and positions the connector closer to where the B generator wires are on my installation. Be sure you install it, whichever way you mount it. See the attached photos.

PXL_20250828_202749336.jpg PXL_20250828_202726335.jpg Bracket 19.png Bracket.png
 
After I read your post, I went out and looked in my leftover/extra parts box, and found that bracket in a small cardboard box that was part of the engine package. I must have ignored it, since it wasn’t mentioned in the KAI. I’d always thought the “floating” connector under the cowling was a little wonky, so glad to have a good fix. Thanks Tony!
 
Wow -- that bracket didn't come with my kit.... maybe I can make one. Thanks for the notice and the photos!
 
Wow -- that bracket didn't come with my kit.... maybe I can make one. Thanks for the notice and the photos!
If you do decide to try and make one, Rotax was nice enough to include detailed dimensions in their Service Instructions.
Screenshot 2025-11-05 at 11.13.39 AM.png
 
This bracket is only for those with the newer style circular connector (as shown in Tony Kirk's photos above). This doesn't apply to those with the older rectangular connector.

Older connector:
Screenshot 2025-11-05 at 11.02.43 AM.png

However, those with the older style connector should refer to this thread (https://vansairforce.net/threads/rotax-912is-regulator-b-wires-melting.228371/) to see what the signs of a failing connector look like. This is likely why Rotax decided to implement this connector change. I'd recommend adding this connector to your inspection checklist.
 
Last edited:
This bracket is only for those with the newer style circular connector (as shown in Tony Kirk's photos above). This doesn't apply to those with the older rectangular connector.

Older connector:
View attachment 101299

However, those with the older style connector should refer to this thread (https://vansairforce.net/threads/rotax-912is-regulator-b-wires-melting.228371/) to see what the signs of a failing connector look like. This is likely why Rotax decided to implement this connector change. I'd recommend adding this connector to your inspection checklist.

It's almost 1 AMU* if you buy the round connector from Rotax. See link in first post.

1762384275374.png

*One Aviation Monetary Unit = $1,000.00 USD!
 
It's almost 1 AMU* if you buy the round connector from Rotax. See link in first post.

View attachment 101347

*One Aviation Monetary Unit = $1,000.00 USD!
The ridiculous cost is why I haven't upgraded mine yet. I just inspect it whenever I pull the top cowling off. However, this thread has me wondering if I should go ahead and replace it.

Looking at your pictures, it appears the part number on the connector is RT06164SNHEC03. This is an Amphenol part available from Mouser in single piece quantities for $28.61. I'd still need the mating connector, 3 pins, 3 sockets, and 2 plugs for the unused holes. That brings the total up to around $70. Add in tariffs, taxes, and shipping and it's about $100. Still expensive, but better than Rotax pricing. I have no idea what Rotax is adding to justify a five hundred dollar markup.
 
Back
Top