View Full Version : Should I Get a Depth Finder??

Shoemaker Mobius
02-24-2005, 06:40 PM
I have had my 2004 Mobius LSV for one year now. We primarily used it on a very even depth lake in Austin that is more of a river than a lake (Lake Austin). This year we plan to branch out to some of the other lakes and rivers in the area. It was highly recommended by several boat owners that ride these other lakes, that I get a depth finder for the boat. My dealer has a Navman unit that installed will be around $325. If I were at all mechanically inclined, I would install myself. But, that's not going to happen. This dealer and service department have been extremely helpful and professional, so I like to give them as much business as possible. Is a depth finder at $325 installed high?? What's reasonable from a dealer. Any thoughts are welcome.

02-24-2005, 09:57 PM
I would definitely get a depth finder; not one of the simple in dash 3 digit LCD ones either. I don't see how they give enough information with just a number. I'd recomend a fish finder/depth finder style that shows a contour map of the bottom. Huminbird makes a basic model for around $100, and I don't see how anybody would charge more than $200 for an install. On my Mobius XLV I installed an earlier version of the Garmin GPSMAP 178 Chartplotter/Sounder(sells for around $425) that combines GPS and fish finder/depth finder. The GPS is cool at night at unfamiliar lakes and just as a gadget as well. Mine also has a computer link so I can download detailed information on the lake like shallow water hazards and fishing hot spots into the unit.

To tell if the $325 price is high you really need to give the Navman model ID. But considering that the options are either finding the bottom with a sonar unit or with the boat hull and running gear, just about any price is good.

Good Luck

02-25-2005, 05:34 AM
Gotta have a depthfinder.

Mine is a humminbird 400TX. Multicone sensor. Gives good bottom profile. Can see the slope of the terrain change in front of the boat, which is real useful at low speeds.
Cost about $250 several years ago. Has a screen that shows stuff graphically. Better models exist these days. Search on this forum and you will find more references to mine as we posted about it a few times over the last 2 years.

A dial gauge is ok, I prefer a set up that gives more info.

02-25-2005, 09:23 AM
Once upon a time a bright young fellow bought a brand new $250 stainless steel prop for his little boat. He took his bright and shiny new prop to a lake he was very familiar with. It was a large deep lake and they would not be out long, just long enough to test out the new prop so there was no need to hook-up the fish/depth finder.

That little gash in the not quite as bright and shinny prop reminds the slightly brighter and slightly older fellow to always use the depth finder, always.

The real question here is - are folks using through hull technology so that you do not have to attach the sensor external to the boat? I am tapped out for toys this summer but next year I am with Steve GPS, bottom contour, and depth.

Steve, are you using through hull sensors?

Oh, set the depth alarm. I assume the Std Moomba depth finder has that.

Fish finders can also give you water temp and battery voltage. Useful if you run a second battery for the radio.


02-25-2005, 09:24 AM
Actually, Does anyone know it the depth finder that comes std is through hull or external?

Shoemaker Mobius
02-25-2005, 09:53 AM
The pricing I was quoted was approx. $149 for the Navman depth finder (which my service guy rates equal to or better than the $199 Lowrance model they also have) and $189 for installation. Give the approx. $325 for this, would it make sense to upgrade to something more than a depth finder? I would assume the $189 installation would probably be the same regardless of the depth finder so I would just be paying for more/better features. What should I look for? From some of the postings it sounded like some type of graphic display is valued. I'd rather not pay for GPS since if I get one I'll probably want a portable one. What else??

02-25-2005, 08:01 PM
Originally posted by smokedog2

Steve, are you using through hull sensors?


Yes, I'm using the provided sender in a through hull set-up. The manual said it could be used either attached to the transom or as a through hull.

The standard Moomba sender is a through hull. I was able to look at one at my dealer to see where Moomba mounts the sender since location is very important to get good readings. You should also take the boat out after you have the head unit intalled and powered up, and test different locations in the bilge area for best transmission. You just need a ring of weatherstripping to make a small "pool" for the transducer to sit in. That way it gets a gapless connection to the hull the same as epoxy when it is permanantly mounted.

Good luck

02-25-2005, 11:24 PM
You should get a depth finder if your interested what's underneath ya. I do. I boat the Columbia and Snake Rivers here and its always good to know as the bottom changes. I like to ski where no one else is so running where most boaters won't venture is a plus and a depth finder is necessary as we're running in 3 feet of water in places. We hear enough prop smacking from the beach which keeps them away. I have always used the 3" guage and they do fine for me. The graph type trends the bottom but I don't think may predicts whats coming up going 20-35 mph. I bought the boat used and I had to switch the depth gauge located by the throttle to where the volt meter is located. I was more interested in watching the river depth change than the voltage on my alternator. The guages are cheap and the installation should be also as all is required is a 3" hole and glue the transmitter to the inside of the hull usually behind the transmission.

02-26-2005, 07:08 AM
Epoxied to the inside of hull near where prop shaft passes thru. I'll attempt to take some pictures today and post them this afternoon. ( last time I tried, I dropped a camera in the bilge and broke it )

Hull is single-wall there and only there , and my sensor isn't recommended for double-wall. Its for single wall or transom mount. A bronze sensor is also available from hummingird that can be mounted thru a hole bored in the hull --- too radical for me.

The humminbird has low wattage, so its not anywhere near as powerful as the lowrance or garmins, so I can't accurately spot fish. Not sure about the gauge type. Downside is the graph-type unit needs to be mounted somewhere. Gage type is a much cleaner installation. Graph type sticks out as an odysey on the dash. Oh well.

Bubbles from prop wash interfere with the readings, so mine didn't work when mounted to the transom. Read the instructions after I mounted it there the first time, then had to move it to the inside of hull. Transom mount must then be way off to one side or the other for it to work at all. Transom mounts are recommended for ouboards or outdrives where they can avoid the entrained air.

But, it does a great job with bottom profile, even at high speed. So, at 35 mph, you are watching for dramatic slope change and listening for warning beeps that indicate dramatic slope change, plus you are reading digital depth. Works for us.

james yarosz
02-26-2005, 08:29 AM
I have a Lowrance with the external sensor.I mounted the sensor on the transom all the way to the port side.It seems to work fine.I wanted the water temp. and speed and distance features to work,and they won,t with a thru hull.I like to know the water temp. before I jump in.;)