Mounting a fish-finder transducer on a Cajo rigid hull
All three Cajo rigid hulls — Outpost 100, Outpost 128 and Terra 116 — use the same transducer cavity, the same size, with the same two brass inserts. It's sized for transducers up to 12" long, which covers the large side-scan units.
The one difference is where that cavity sits:
- On the Outpost 100 and Terra 116, it's recessed into the bottom of the hull.
- On the Outpost 128, it's on the underside of the removable electronics pod — same cavity, same inserts, just on a part you can lift out of the boat.
Two things live in that cavity:
- Two threaded brass inserts that take M5 hardware. This is what a transducer bracket bolts to — you never drill the hull.
- A scupper hole alongside it. The transducer cable runs up through the scupper to your head unit, and can feed into one of the boat's Power Plates with a thru-hull wiring kit if you want somewhere to store the excess cable.
You supply the bracket, and it depends on your transducer
This is the part that trips people up. Every fish-finder brand ships its own bracket, and they're all cut to different patterns. A Lowrance Active Imaging bracket is not a Garmin GT bracket is not a Humminbird Mega SI bracket, and most of them are transom or wall mounts rather than flush mounts.
So there is no single Cajo bracket that fits every transducer. You pick a third-party adapter made for your particular unit, and bolt it to the two inserts.
The shortcut: look for Vibe Shearwater 125 adapters
Our insert pattern is the same as the Vibe Shearwater 125's, and our cavity is larger than anything Vibe produces. So an adapter listed for the Shearwater 125 should bolt straight onto any of the three Cajo rigids, with more clearance than it was designed for.
That matters because "Shearwater 125 transducer mount" is a far larger catalogue than anything Cajo-specific.
Brands worth looking at
These are starting points, not endorsements — check the fit against your own transducer before you buy.
| Where to look | What they make | Good for |
|---|---|---|
| Yak Hobby (Buford, GA) | TightTuck knuckle brackets for the Shearwater 125, bolting to the two inserts with M5 hardware. Separate SuperMount brackets for the Lowrance Active Imaging 3-in-1 on other hulls. Takes custom orders. | Most transducers. The first call if nothing off-the-shelf matches. |
| BerleyPro | UNI TRANS and Vibe-specific mounts. The UNI TRANS lists the Lowrance Active Imaging HD 3-in-1, Totalscan, Garmin GT51/52/54/56 and Humminbird XM9. | Large side-scan transducers. Note the UNI TRANS is built around a rectangular plate, not a two-bolt pattern — ask them about adapting it. |
| Hydra Concepts | A universal Shearwater 125 transducer mount, adjustable to 2.5" width. | Skimmer and smaller side-imaging units. Stock comes and goes. |
| Thingiverse | A free 3D-printable bracket cut for the Shearwater 125 and the Lowrance Active Imaging 3-in-1, using M5x20 stainless hardware. | Anyone with a printer, or a print service. |
Does mounting a transducer affect the warranty?
No — bolting to the factory inserts and running the cable through the scupper is what they're there for. That's normal supported rigging, the same as mounting an accessory to a gear track.
Drilling new holes in the hull is the thing to avoid. Between the transducer cavity, the scuppers and the three Power Plates, a full electronics install shouldn't need it.
Still stuck?
If you need any more assistance on this, get in touch with support and we'll help you work out what fits.