Garmin Depth Finder Transducer

Status
Not open for further replies.

Century Bay

Member
Joined
Apr 5, 2020
Messages
15
Fluid Motion Model
R-21 EC
Hull Identification Number
FMLC2808G819
Vessel Name
Century Bay
We purchased a new Cutwater 28 in the fall of 2018. Generally we are pleased with the boat although we have not been able to use the boat much for a variety of reasons (30 hours as of today). We had an appointment with the dealer we purchased the boat from to address a number of what we hope are minor issues but due to the Corona virus we are on hold.
One of the problems we are experiencing is the failure to get a depth signal. After trouble shooting with Garmin and the dealer over the phone it was suggested that the liquid may have leaked out of the transducer.
Today, while at the boat doing some clean up I decided to look for the unit and see if there was any visual leakage. I found the unit as advertised near the shower sump pump.
However, what I discovered was the unit fully detached from the hull. It appears that the unit was glued to the hull and it had came completely off.
Is this standard design for the Cutwater 28 and what should be done to remedy the failure.
Thank you
Century Bay
 
Found this using search function....


Re: Through hull Transducer for C-24
Postby MarcoArias on Tue Oct 01, 2019 8:30 pm

Hi,.

For your transducer to work properly, there must be a fluid medium. At the factory, we like to use RV antifreeze. This eliminates any issues that may occur if the boat is ever in freezing conditions. As previously mentioned, it is wise to monitor the area around the transducer for leaks. This is especially true around the mounting area. To remount the transducer, make sure the area is properly cleaned, add a bead of seal only where the transducer will make contact with the fiberglass, and press the transducer onto the seal. Wait to fill it until the seal has properly cured. We use Sikaflex 291. Feel free to send me an email if you have any questions.
 
Please excuse my ignorance, but I've just got to ask - Why in-hulls instead of thru-hull transducers? I've had in-hull, transom mount and thru-hull and by far thru-hull is superior IMO.

Both the in-hull and transom mount had difficulties at speed and with depth over 800'. Since I fish at Norfolk Canyon finding contours at 1000 feet or more is important. The in-hull lacked water temperature readings - again important for fishing. I've caught more tuna on a temperature break than anywhere else.

I know they cost a bit more, but the value seems worth it to me. Also, my in-hull had to be repaired multiple times over the years and I was ready to put in a thru-hull just to avoid the problems with the in-hull, but I decided to sell the boat.

Guess I don't understand why the choice for in-hull? I know I'll never own one again, or if I do, it will be one of my first projects to install a thru-hull.
 
Century Bay":gq961ljl said:
Today, while at the boat doing some clean up I decided to look for the unit and see if there was any visual leakage. I found the unit as advertised near the shower sump pump.
However, what I discovered was the unit fully detached from the hull. It appears that the unit was glued to the hull and it had came completely off.
Is this standard design for the Cutwater 28 and what should be done to remedy the failure.
Thank you
Century Bay
I had the same issue with my RT-27OB. Based on conversations with the factory, it looks like the plastic transducer mount was not prepped properly before installation. The mount needs to be scuffed up with 60-80 grit sandpaper to remove the shiny surface. My transducer mount surface was shiny. I used 60 grit sandpaper and scuffed up the hull where the mount attaches and the mount itself. I then cleaned up the hull and mount with Acetone. I then attached the mount to the hull with 5200 and it has held since.
 
There are two ways that fluid motion mounts the transducer. Dry mount directly to the hull or cup mounted ( a transducer cup is glued to the hull and the cup is filled with propylene glycol (RV antifreeze). There have been many threads about this posted. I'm posting the instructions for the mount.
https://www.google.com/url?sa=t&rct=j&q ... g75bhwkOcj


There have been a number of Tug/Cut owners that have had the dry mount fall off and a number of cup mount find the cup dry of fluid. Each was a result of improper installation. This is one of the areas that Quality Control needs to step in and give training to installation technicians. It's an easy process to install but it must be done correctly. Airmar has three recommendations for material to glues the transducer in place.
Mounting:
Sand/grind the fiberglass until rough. Clean the fiberglass, then mount with:
1. Fiberglass Resin (best choice for long-tern adhesion)
2. Fusor® 100EZ / T10.
3. 3M 5200,
 
HookedUp":31vxniun said:
Please excuse my ignorance, but I've just got to ask - Why in-hulls instead of thru-hull transducers? I've had in-hull, transom mount and thru-hull and by far thru-hull is superior IMO.

Both the in-hull and transom mount had difficulties at speed and with depth over 800'. Since I fish at Norfolk Canyon finding contours at 1000 feet or more is important. The in-hull lacked water temperature readings - again important for fishing. I've caught more tuna on a temperature break than anywhere else.

I know they cost a bit more, but the value seems worth it to me. Also, my in-hull had to be repaired multiple times over the years and I was ready to put in a thru-hull just to avoid the problems with the in-hull, but I decided to sell the boat.

Guess I don't understand why the choice for in-hull? I know I'll never own one again, or if I do, it will be one of my first projects to install a thru-hull.


The thru hull is a better choice and used more in larger vessels and fishing boats. There are issues with thru hull used on a trailerable boat. The best area to install a transducer may be in the same area as the bunks. The last thing you want is the transducer laying on a bunk. Transom mounts on Rangers and Cutwaters don't work well either. There is to much stuff going on in the aft section of the boat ( to much turbulence ) so the transducer doesn't see "clean water". If the in hull installation is done properly the performance is good. That is the biggest issue found with Tugs and Cuts installation. Once installed properly the performance seems to be ok. I had a installation issue when I purchased the boat 2016, I repaired it and have had no issues since.
 
The Aimar P-79 in-hull transducer is a entry level transducer and not designed for mounting in vessels with a hull thickness more than 5/8in, I think you will find that most boats from fluid motions will be at the max fiberglass thickness or greater. With the signal shooting through this much material you will loose performance.
The thru-hull (low profile) transducers with less than 1/4in outside of hull, are designed for trailers, and can sit on rollers or bunks with out damage! Though I wouldn't recommend and if bunks were in the way of placement, the bunks could be moved a few inches with no problems! You do have other hull fittings on your boat that require clearance of rollers/bunks.
With the transducer being the most talked about problem on this site and one of the most valuable assets on the boat! I'm surprised that fluid motions has not upgraded to a more reliable product!
Bob
 
bob daily":uhudq0ru said:
I'm surprised that fluid motions has not upgraded to a more reliable product!
Bob
I'm not, it is cheap and quick/easy to install and works well enough for the majority.
 
For only those that want to listen, here's my rant... but don't say I didn't warn you!

First, this is a great forum where one can sift thru the posts for your needs then wade through the respondents for their experience and/or knowledge of the subject. We all recognize those who have a firm grasp on the subject and share their valuable information, although all experiences give us perspective.

BB marine is a voice that when he talks, I listen! I love you man!

I previously owned a PNW-made SeaSport Explorer... a great fishing boat and an average pocket cruiser. I shifted gears when buying our R27-OB... a great cruising boat and an average fishing boat.

Clean water under the hull is essential, and without it your transducer has clutter. So mounting location based on your hull's "signature" is critical. Once you identify the best installation location for clean water, then figure out transducer spec requirements for your needs, and mounting style for your boat.

We became boaters-over-fishers with this boat. We have a Garmin GT15M-IH in-hull with Chirp technology and supported by our Gpsmap 7612xsv plotter. If you fish, chirp gives more samplings and greater separation/definition of what's below your boat, which is essential for fishing. This is a 600w unit and is rated for 1900 feet, although I can't verify that depth. I don't care, I draft 39 inches!

I would guess the majority of Tug/Cut owners are also boaters-over-fishers, so Fluid Motion builds to the common denominator. I don't consider their installed components cheap, but if I want a component with better features I replace it, e.g., my VHF radio.

I likewise have been frustrated with some of the quality control issues on our boat, but RT has made a legitimate effort to correct any problems I've encountered. Hopefully they will continue to improve their product QC.

Is Fluid Motion perfect? No, they're not, but no boat builder is. I do consider FM a good partner that I have access to, and together I feel we have achieved the best R27-OB on the water!

Good luck with your transducer!

Bob
The Doghouse 2
 
Thanks to everyone. I really appreciate the feedback. Wow! what a great forum. Going forward I can see that I will need some help in fixing the build issues on our C28.
 
Found the P79 transducer, inside the shower pump on the fwd Cabin floor, totally dry without a drop of Anti-freeze. Put 71mls into the cup and the depth sounder works beautifully. One problem fixed and many many more on the list. Shouldn't buy another used boat.
 
We noticed that our newly purchased 2012 Cutwater 28 had poor sounder readings, especially with the engine in gear. We traced the transducer wire back to an oil bath above the propellor below the folding seat in the stern. We added mineral oil, the sounder started working, but not good enough to see fish. We eat fish. So I pulled out the Airmar transducer, rerouted it to beside the shower sump box immediately below the forcasle steps. I built up a little platform with fiberglass mat and ordinary resin to get a surface parallel to the ocean floor, roughed it up, and ordered a little packet of Lowrance 2 part epoxy which is not supposed to have any air bubbles. Ouch that was expensive for what you get, about 2 tablespoons for $47. It glued her down solid. On our trip to Desolation Sound last week the sounder read down to 1400 ft.
 
Yes there is no way that a transducer works well aft of the step in the hull. If you look at the bottom of that hull there is a lot going on. Every strake , prop tunnel, the "Bubble" under the engine, all disturbs the water. The forward location by shower sump seems to be the best place to mount it. I don't use it for fishing or deep water readings. I'm more concerned with the accuracy in shallow water. As long as there is a good zero void area with zero void adhesion the transducer should read accurate. The only issue I have had with the transducer was the o-ring was not installed and the fluid leaked out. I installed an o-ring poured some propylene glycol in the cup 4 years troubled free.
 
when the p79 is installed properly in the cutwater in the shower pump location it can hold bottom down to 800 feet and I can tune the older 5212 garmin with the default GSD22 control unit to easily display fish.
 
Status
Not open for further replies.
Back
Top