Thank you to my big brother, Nick for helping me with this project! See a photo of us at the bottom of this post.
Article written from first hand experience of WaveRunner owner, and reviewed and edited by marine mechanic.
What You’ll Need to Get Started
Raymarine Dragonfly 4 Pro – or a fish finder of your choice
Black Electrical Tape
Why we wanted a depth finder
Recently, my husband and I decided we wanted to have a depth finder on our WaveRunner. We thought it would be exciting to know depth when we are in open water. But, after we suddenly ran aground in a lagoon (normally around 2-3 foot deep), we thought it would be useful to prevent further dangerous moments. After weeks of research, I landed on the Dragonfly 4 Pro! In this blog post, I will tell you a little bit about the Dragonfly, and provide complete instructions for mounting it on a personal water craft (PWC) like a WaveRunner, Sea-Doo or Kayak.
The Raymarine Dragonfly 4 Pro has a 4” touch screen color display GPS/Sonar, Dual CHIRP sonar, Wi-Fi and more. All these features were more than we could ask for! In addition to finding depth, we can view fish and the landscape of the ocean floor in different ways. My favorite view is heat vision, because it gives a more colorful picture of the marine life below. But my husband’s favorite part is having a GPS to help us navigate our cruise. We also love that it shows us depth so we don’t venture into areas that are too shallow.
View the Raymarine Dragonfly 4 Pro on Amazon
Why We Chose the In Hull Transducer Mount
There is an extreme deficit of information online for installing depth finders on jet skis which became my motivation for writing this blog post. Thankfully, my big brother Nick is a semi-pro bass fisher and a self taught marine mechanic. He’s picked up knowledge from 10+ years of owning competitive boats and outfitting them all with fish finders and transducers. He installed our depth finder and advised on this article.
Many articles only discuss two primary positions for mounting the transducer: 1. Transom Mount (pictured left below)- attached on the external end of the WaveRunner next to the foot step and 2. Through Hull (pictured right below) – Inserted into a hole in the bottom of the watercraft so that it is flush with the external fiberglass.
We immediately knew the Transom Mount would not work for us, because we often beach our WaveRunner and cruise through low tide waters. We felt this position was too great of a risk of ruining the transducer.
We heavily considered the Through Hull mount, but we had two reservations with this method. First, to go this route, you really need a brass transducer which does not come stock. It has to be ordered separately and is an additional $300. Furthermore, the labor required to install this way was quoted to us at $500. Second, we were really nervous about cutting a hole in the bottom of the ski, and we didn’t know of anyone we could trust enough to do that.
Unable to make a decision, I reached out to my bother, Nick. Honestly, I don’t know why I didn’t contact him first!
Nick told me that as long as our ski is fiberglass, we could glue the transducer in the bottom of the hull. I was surprised he recommended that because all articles online indicate that you will lose considerable performance with an in hull mount. Nick said that he glues all his transducers in the hull, and the performance decline is minimal because the fiberglass is so thin. He also mentioned that the fiberglass on our ski may be even thinner than a boat! The thin material makes the in hull adhesive mount quite suitable for personal water craft like a WaveRunner, Sea-Doo, or Kayak.
In Hull Transducer Installation
Once we agreed on an in hull mount, we decided to glue the transducer directly below the driver’s seat. There was a nice space there with no existing parts mounted that seemed to be perfect for the transducer. This placed it far away enough from the motor jet that it’s signal wouldn’t be disrupted by the vibration of the engine. Here is a photo of the transducer after it was installed:
We used J-B Weld 8272 MarineWeld Marine Epoxy – 2 oz. and pointed the thin end towards the front of the jet ski while aiming the bulb end toward the back. When using marine epoxy the inside of the jet ski has to be completely dry. We had to tilt it back on the trailer to get some water out from a previous wash. After you set the transducer the epoxy has to dry for 6 hours. If it moves or gets wet, the transducer will not adhere appropriately.
View J-B Weld 8272 MarineWeld Marine Epoxy – 2 oz. on Amazon
Routing the transducer and power cables
Our approach to mounting the cables was to be as minimally invasive as possible. To accomplish this, we made use of the pre-existing structure of the WaveRunner steering column.
First, we removed the plastic panels around the steering column using an allen wrench. This revealed the structure of the steering column. As shown in the photo below, the structure includes a rubber boot (water tight hole through the hull) and the main steering mount plastic. We needed to get the cables routed through the rubber boot and then up through the plastic of the main steering mount.
There were already cables run through the rubber boot to the steering column, but there was plenty of room for the small depth finder cables. We had to stretch the rubber but we were able to push the depth finder cables through the boot as well. Because of this rubber boot, we were able to avoid drilling into the hull.
Next, we needed to get the cables through the main steering mount plastic. So, we drilled a small hole through the plastic directly under the speedometer cluster in the far left corner. Note: Speedometer may need to be lifted to drill this hole.
Once we drilled this hole, we were able to route the cables through the main plastic of the steering column. However, we needed to clamp the speedometer cluster panel back down and still have room for the cables. So, we used the drill to route a small groove in the speedometer cluster’s plastic cover. This allows the speedometer cluster to clamp back into place without putting pressure on the cables. (See photos below).
We ran the cables through the groove in the speedometer cluster’s plastic panel and clamped it back into place securely. When we finished, the depth finder cables were easily accessible at the steering column.
This approach makes the modification unnoticeable and compliments the design of the steering column.
Mounting the display
The Dragonfly 4 Pro comes with a display mount, but Nick suggested an aftermarket mount called the RAM Mount Marine Electronics Mount. The Ram Mount has a much smaller base which made it easier for us to find a better position for the depth finder on the WaveRunner. Moreover, the Ram Mount is designed to handle normal vibrations of the vessel and rough water conditions so that the display is always clear and stable for the operator. Plus it’s very reasonably priced! I don’t recommend proceeding with mounting your depth finder without having this mount.
View RAM Mount Marine Electronics Mount on Amazon
The Ram Mount required two small holes. We placed it on the left side because my husband is left handed. Thanks to the WaveRunner Design, this did not impact any water tight areas.
The depth finder has its own power lines that are supposed to connect to the Jet Ski battery; however, these were only about 18 inches long. We needed extension lines (red and black) to help the power lines reach the battery. We took the red wire and spliced it with additional red wire and did the same with the black wire sealing these splices with electrical tape. So now, the end of the wire, could reach the battery.
We added a Blue Sea Systems Waterproof In-Line ATO/ATC Fuse Holder to the red wire. This ensures that if there were a power surge the depth finder would shut off.
View Blue Sea Systems Waterproof In-Line ATO/ATC Fuse Holder on Amazon
To connect the black and red wires to the battery, we removed the bolts holding down the circle clamps. There were existing cables running to the battery that power the Jet Ski displays. We lifted those and inserted the depthfinder power cables under them. We replaced the original power cables and then screwed the bolts back on.
After we were finished, we re-attached all the plastic paneling on the steering column. We took the WaveRunner out the next day and played with our new toy! It works great!
Transducer mount: We don’t think we miss out on any performance from the in hull mount. It works really well at speeds up to 15 mph, we have a perfect view of the ocean floor and our depth. The GPS works at high speeds and slow speeds.
Cable routing: We are really happy with the placement of the cables. We are pleased that we could use the existing “rubber boot” to get the cables through the hull without drilling. The Yamaha steering column was easy to work with as well.
Mount positon: it is in the perfect spot and the RAM Mount is performing like a champ! We have no fear of knocking it off and we maintain clear visibility through the vessel’s vibrations and rough waters.