Putting electronics in 400 Sundancer - thru hull or transom transducer?

Tiki Sea Rays

New Member
Oct 28, 2014
5
Tiki Island, TX
Boat Info
1999 400 Sundancer
2007 290 Sundancer
Engines
1999 - none
2007 - twin big blocks
Hi all - This is my very first post so I hope I'm making it a good one. We just acquired a 1999 400 SD and it only has the basic electronics it came with. We'd like to put in a GPS or radar and I'm wondering what the proper transducer placement would be - thru-hull or transom mount? Or are there other options? The boat is in saltwater, if that makes a difference. Your advice is appreciated. Many thanks.
 
Congrats. and welcome to the club!

I've never seen a 400DA (SD is the designation for the "Sundeck" bowrider) without a transducer. Are you sure you need to add one?

If you do, a transom-mount would be a big red flag at resale time - that's very uncommon in larger boats.
 
Hi Mike, I don't know. If it's below the water line, then I haven't seen one. It'll be coming out of the water soon for a bottom job so if there's one among the barnacles, I'll see it then. I'll be honest - I didn't think the boat was sophisticated enough to have a transducer since there's a place at the helm for reading nav charts (hence the need for electronics.) The boat has no engines - I know, I'm putting the cart before the horse - so drilling any holes would be done when the boat is out having the bottom job done. Thanks, Maryann
 
I didn't think the boat was sophisticated enough to have a transducer since there's a place at the helm for reading nav charts (hence the need for electronics.)

The chart area was standard on the 400DA throughout production from the '97 model year into 2000. Some never had navigation electronics installed, but I've seriously never seen one without a transducer. Mine is mounted just fwd of each engine (a speedo wheel on one side, sounder on the other).

The boat has no engines

wow. well, fwd of where your engines WOULD be. :grin:
 
Thanks RollerCoastr for correcting my Sundancer abbreviation - my newbie is showing! Not sure what I need to add, really. I'm just trying to get a jump start on what to do when she's out of the water. Any GPS or radar advice is totally welcomed. Hopefully getting repowered soon since we got her minus the engines.
 
Magic. No, Sea-Ray-ously......the former owner, a few doors down the canal from us, had his boat guy come down and pull them out to supercharge them and then got divorced and we now have a beautiful boat. You are now up to speed.
 
Tiki, Congrats on the new boat and the fun you're going to have with it. And welcome to CSR. This is a good place to get your questions answered.

I think the surprise about the boat being in the water without engines had more to do with how they plugged the holes for the prop shafts, etc.

What I would suggest you do is find a reputable marine electronics place and pay them a visit. You're going to want more than a depth finder in that boat. A marine electronics dealer will be able to show you various radar systems, chart plotter systems and discuss with you what is needed to get them to "talk" to each other.
 
Thanks for the advice, Gofirstclass. And nice boat. I have a funny feeling I'm going to be a card-carrying member of the Hole in the Water Club as well. I'm sure there will be more questions...like, does docking get easier as the boat gets bigger?
 
Just so you….or the electronics guy you choose……… know, Sea Ray has anticipated the need for transducers beyond the typical depth,speed, temp tridata instrument. There is an area in the hull, usually where the forward bilge sump is right behind the main bulkhead that is solid glass and this is where any added transducers should be positioned.

Many current generation plotters now have optional bottom machines available in the same dash unit. For a few hundred $$, you can ad a very sophisticated bottom machine that you can see on your plotter with a split screen. This saves adding another display to a crowded dash, but does require an additional transducer.
 
In no way should you be mounting a transom mounted transducer to a 400 Sundancer. you need a thruhull and fairing block
 
Tiki Sea Rays
Your boat should have two transducers originally installed; one for depth and one for speed and temperature. They are both located in the engine room forward bilge under the AC water pump and strainer.

The original ones are rather old tech and best to replace them with new and up to date. I replaced mine with Airmar NEMA 2000 Depth/Temperature and a sonar. Both feed the NEMA 2000 backbone and new Garmin Instruments.
 
Tiki Sea Rays
Your boat should have two transducers originally installed; one for depth and one for speed and temperature. They are both located in the engine room forward bilge under the AC water pump and strainer.

That's interesting - mine are basically under the fwd end of the shafts. I have a bilge pump and float switch in the area you describe.
 
That's interesting - mine are basically under the fwd end of the shafts. I have a bilge pump and float switch in the area you describe.
That indeed is interesting. I also have a bilge pump and a thru-hull for the AC water in that area.
 

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