Fish Finder or Depth Sounder? Need advice.

[John in Valley Forge]

I am trying to decide between a fish-finder and a depth-sounder for my recently acquired1999 Sportster 1800. Having no prior experience using either, I am seeking advice.

Here are some random facts that may or may not effect my decision

I will run the boat mostly in a river that is less than 10’ deep. Much of it is less than 5.

Much of the time I am pulling kids on a tube, usually above 20mph (max speed is 45mph). This is done in areas that I know are the deepest.

I expect to take the boat to salt water bays (Jersey Shore and upper Chesapeake) as well as fresh water lakes.

My budget is $125 or less (based on the cost of a Lowrance X-4 Pro Fishfinder at WallyWorld). Much more than that and I risk getting the “are you spending more money on that *#&@ boat again?” look.

I do not fish from the boat (yet).

Need vs Desire: I need to know how deep the water is. I desire to know what the bottom of the river looks like (especially going through a particular channel).


From what I have read online, there seems to be a speed limit in the depth readings of a fish finder. Depth-sounders do not seem to have this problem. Or do they? I do not know.

I am hoping not to have to drill holes in the hull or transom, I’d rather “shoot through the hull”.


Thanks in advance for your responses.

 

[mattadams66]

i just installed a humming bird 170 on my 98 sportster 1800. it was $100 at basspro. I was like you wanting a depth gauge but the gauge itself was upward of $100 so the dual finder and depth gauge seemed like a good idea. At max speed the finder did have times where it would lag and have no signal showing lake terrain however at speeds where you would be skiing/tubing it works great. Just know you wont get great detail of trees and logs with this finder however you will be able to see depth and must obstructions. Also i did drill holes on my transom and used a good marine silicone sealant and have not had any issues with links.

hope this helps.

 

[John in Valley Forge]

I found the Lowrance X4 Pro at Cabella's for $99 and they have it in stock.
Sounds like an after work road trip!

 

[John in Valley Forge]

I decided that to try it out and to map the river channel near the old dam, I am going to mount the transducer on an old boogie board and drag it alongside the boat. Kinda like that side-scanning sonar stuff.

 

[biffdotorg]

I too made that debate with the Hawkeye the same price as the X4 Pro. It went on sale at Fleet Farm here for $85 and I now have it installed. Check out our other threads on this project. Worked great. Don't mess with the boogie board, unless that transducer is more solid, you won't have any luck.

You can get the suction cup mount from lowrance as a temp mount. They are great on fiberglass. Go with the epoxy in the hull and you will not go wrong. Pics are on here and my personal blog. Good luck!!

http://biffdotorg.blogspot.com/2011/06/who-wants-cheesy-depth-guage-when-you.html

 

[John in Valley Forge]

So I got the fish finder on Friday night.

Saturday I snaked the wires from the engine compartment up along the side, drilled a hole and mounted it on the dashboard (between the cup holder and the gauges). I tapped into the radio for electricity (I don't use the radio when driving).
I ran the transducer out through the air vent so I could drop it off the back. I temporarily hung it on the transom using a big suction cup.

It worked eh, ok I guess. gave what seemed like reasonable readings (they were real close to what my buddy was getting on his factory installed depth gauge.

Parked the boat later and tried the plastic bag of water in the engine well. The first thing that happened was that the baggie got a hole in it, but it still held enough water to make a "bed" for the transducer to sit in.

Odd thing though, it read 8 feet, but the water was only waist deep (3 ft maybe). The bag was sitting in a depression in the hull, next to the bilge pump and the drain plug. If I held the transducer while standing in the water behind the boat, it read 2.8ft which sounded right. Back in the boat on the bag of water it said 8. I tried the bag of water in a different spot, forward of the engines. almost under the gas tank. Again I got the 8 ft reading.

I am now thinking that the incorrect reading is due to the thickness of the hull and I need to mess around with the gain and sensitivity settings. Does this sound right to anyone else? I don’t want to epoxy it in place if this error in depth readings is something serious.

I’d like to test it in 30 feet of fresh clear water like it says in the instructions, but I think the closest place that has that is over an hour away.

 

[biffdotorg]

Which one did you end up buying? The X4 Pro? It should be set to Auto sensitivity from the factory. That worked well for me through the hull.

We also had issues with the bag, so we put a bit of water in the ski locker, and set the bag on top of the transducer to hold it in place and it worked great. After the full install, I did adjust the sensitivity a bit, but otherwise left it mostly at factory settings. That's almost worth a call to Lowrance if you cannot get it figured out. That sportster 1800 should not have any different hull material than the rest of us.

The only other thing I can figure is if you or a previous owner may have had some hull damage there and it had been repaired. That would mess with the density and ultimately effect the transducer's performance.

 

[John in Valley Forge]

I got the X4 Pro ($99 at Cabella's).

I am thinking that the plastic bag thing is probably not the most accurate thing in the world. The transducer is a few inches off the deck surface on the baggie and I cannot guaranty it was pointing straight down. I felt good that I got the exact result with the same bag in a different hull spot.

I assume I place this thing level in the bed of epoxy I make and that its orientation is not critical in the long run (no matter how you put it in, the boat will not always be exactly level).

I could spend the next week just trying to clean the floor of the engine compartment enough to get the epoxy to stick

 

[biffdotorg]

Pressure washer baby!!

I had a buddy hold mine on the bag, then hold it afterwards. That was the only real way. It will sit up fine on the epoxy. It's thick crap!