Garmin 7412XSV & B175M

[Almako]

Hi guys, I just wanted to update the thread that after 7 years of owning a CruiseCraft 625 Explorer I have finally installed a sounder that reads at speed. Some of you would know that I have tried everything.

Started with Furuno FCV628 and P66 on the transom
Changed to JRC FF60 with same P66
Change from P66 to Furuno in hull 520IHD i think it was
Then put in a through hull Airmar 600watt thing with the JRC still on board
Then upgraded to Garmin 7607 (but the older model)
Then tried running the old Navman 8120 that I was using as a plotter
Changed the prop to 4 blade which caused other issues such as how the boat performed, changed it back to a different 3 blade.
All of this to no avail

Installed Garmin 7412xsv with GT51 sounder - still no good
Installed B175M 20degree through hull and it's finally awesome.

If you have one of these craft and are having problems I'd suggest putting a through hull B175M into the hull (20degree) and not 0degree into the bottom plank. You may have a different experience but this is what has worked for me.

Some pics from two trips local Brisbane one solo mission the other with a mate.


b175mm.jpgsnapper.jpg
IMG_3534.jpg
IMG_3593.jpg
IMG_3549.jpg
IMG_3550.jpg
IMG_3597.jpg
IMG_3595.jpgIMG_3594.jpg

[ranmar850]

I'm quite impressed with my B175M , have a look at the thread below titled Axiom 9 pro and B175M. i did mention i may have been looking at the RV-100 by mistake, but, checked this morning, definitely reading through the 175.

[Dignity]

I'm looking to update one of my units later this year, when you say 20 degrees, what does this exactly mean, apologies if it's an obvious question.

[scottar]

20 degree tilted element through hull

[Almako]

Hey Dignity here is an image i borrow from the net.
The tilt is inside the transducer itself so that it can be installed in on an angle.

image 20 degree.jpg

reference:
9 May 2018,https://hudsonmarine.co.uk/products/...y-cable-t70076

[Dignity]

Thanks guys, I understand now that I've had a look at it, is there any reason why it shouldn't be put in the planning plank.

[ranmar850]

Some owners may want to chip in on this but I believe it has not been a success in the past. While it looks like an obvious spot, it gives a very dirty, broken picture, at anything but very low speed, at least on Cruisecraft--opinion is that the planing plank generates a lot of air. A bloke on the WA forum tried it--he went to an enormous amount of trouble, having a 3-d plug printed up to match the transducer dimensions, then made a mould from that, then cutout for the hull glassed in. Had to move a seawater intake in the process also, and work in that very confined space under the well. Results were poor, he was disappointed, and rightly so. A bit of research showed he wasn't the first person to come to this conclusion, he wishes he'd looked into it a bit further.

[Dignity]

My issue is access to the hull either side of the plank is very limited due to the cellular build below the deck. I have one option but it is almost in line with a strake further up the hull.

[ranmar850]

yes, don't you love it when they don't give you many options. You'd think that big thru-hulls weren't a common aspiration in boats like these, rather than being the norm. The space I had on my new boat is clear, across the beam for about 350mm either side of the vee-keel, but very narrow--you had to get it almost hard-up against the transom to avoid having the bronze touch the aluminium fuel tank. I worked on getting it between 2 strakes, but they are not full length strakes, which means the air is probably spreading as it approaches the transom. I was playing with all manual sounder settings during the first run, beautiful picture at low speed, but probably need to go back to Auto-everything for fast travel.

[Almako]

The planing plank was definitely an improvement from the transom, though there was further improvement when installed to the side.
Each boat will be different but that's what I found on mine. If I didn't already have a transducer in the plank I'd probably have put the 1kw there, though the installer at Trymax said it wouldn't fit as it's huge. So that also comes into the equation.

[Getout]

Some owners may want to chip in on this but I believe it has not been a success in the past. While it looks like an obvious spot, it gives a very dirty, broken picture, at anything but very low speed, at least on Cruisecraft--opinion is that the planing plank generates a lot of air. A bloke on the WA forum tried it--he went to an enormous amount of trouble, having a 3-d plug printed up to match the transducer dimensions, then made a mould from that, then cutout for the hull glassed in. Had to move a seawater intake in the process also, and work in that very confined space under the well. Results were poor, he was disappointed, and rightly so. A bit of research showed he wasn't the first person to come to this conclusion, he wishes he'd looked into it a bit further.

I also have a Cruisecraft 625 and recently installed an Axiom Pro with B175M thru the planing plank about 300mm forward of the transom. It reads perfectly at 38 knots in flat water on auto settings, but in rough water at speed, it seems to get air at every bit of chop. (My old Airmar transom transducer is way better at speed.) The display did improve when I slowed down the ping rate. There may be more to learn. I went this way for better results in 50+ metres at sounding speeds. Haven't yet put it to that test.