Question: Garmin Echo 300c transducer placement on a RIB with a Cat Hull?

[OcciferNick]

Hello everyone,

I am hoping that with the vast knowledge base here on Aus fish someone might have a better idea on where I should try to mount my transducer. I have a Garmin Echo 300c to mount on my 4.6m RIB. The boat is used for diving mainly and some general fishing in the bay and when I go on holidays. I've tried researching this on the net and trawling through soooo many posts and pages but cant find a hull that is similar to mine. Here is a photo of the hull showing the water level at rest and also showing the level when moving slowly forward. Obviously the faster I go the lower the water level drops but I don't plan on driving flat out with the sounder on anyway so only recorded these two levels.

After reading the manual I'm still not entirely sure where I should place it. I read that you should place it a certain distance from the motor (motor up in this pic 55hp o/b) and also not near the strakes etc The more I read up on the problem the more confused I bloody get!!! lol

boat transom for upload.jpg

As you can see in the picture of my transom there is no area that is parallel to the ground (water level) and there is bloody strakes everywhere! Is there anyone out there with a hull that is similar and has successfully mounted a transducer on the back? Or should I just mount it on a stainless rod at the back of the back and just keep moving it around until I find a spot that it works and then mount it. Can you do it that way? Sorry I have never mounted a transducer before so trying to avoid mounting it and having to move it again and leaving the transom looking like swiss cheese haha

Thanks in advance,

Regards
Nick

[Swanie1975]

Next time you are out in the boat have someone else drive for you and lean over the back and see where the cleanest flow of water is. Mark it then you will have to play with the height where you still get a clear reading but don't cop loads of spray so your pole idea might work nicely for this stage.

Only my 2c worth but it looks like a very tricky hull to work with. Some of the guys with cats on here might be thinking thru hull transducer but I guess it depends on the budget. Good luck with it.

Cheers Ryan

[OcciferNick]

Thanks for the reply Ryan I actually tried your suggestion and when I looked over the transom I couldn't see any clean water at all that's why I posted on here lol
I think I'll start looking around for the components to temporarily mount the transducer so it's easy to move around. I might take out the gopro and record the water flow and post the link on here!

[John Buoy]

I would start in the extreme keel line of the starboard sponson (when you click on the photo right where the U in ausfish logo is located

[upstart]

There have been a couple of posts around here recently where people have sikaflexed a piece of timber or cutting board type material to the hull and have then screwed transducers into that. Might be worth doing that and then trial and error.

[OcciferNick]

Thanks for the replies everyone.
I think I will start where John Buoy recommends and go from there. Upstart I actually came across the commercial product of what you are describing when researching this problem. I like the idea of not drilling holes in the transom so might go that way when I can find a spot to mount it.
Cheers
Nick

[upstart]

What was the product? Got a link?

[OcciferNick]

The product was called Sternmate
I didn't know if the forum rules would allow me to post the product name that's why I didn't in my last post.
It seems like a good system, glue the plastic block to the transom and the bracket which the transducer is mounted on can be adjusted up and down on the block.