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Discussion Starter · #1 ·
OK,
Tell me if any of you have ever heard of this.

My depth sounder reads fine in my marina and at idle speeds. Once take off and get on plane it reads 2.5 ft everywhere on the lake.

I added a hydrofoil to the OD a couple of seasons ago, could that somehow be creating some kind of turbulence that is screwing up the readings??

Any insight will be appreciated.

Thanks!
 

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Where is your Transducer located? Transom mount or thru hull?

I'm having problems with mine reading as well, mainly while on plane it just goes blank, then comes back on whenever..not consistant. Kinda scary when there are shallow spots out there.

*My Most important equipment on the boat is:
1. Compass
2. Depth Sounder
3. Ship Shore/VHF (for emergencies)
 

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Does your boat have a stepped hull? I know some people with stepped hull boats have problems with the depth sounders.
 

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Any sounder that I've ever had never would work much above minimum planing speed. I'm told that it is because an increase in hull speed creates turbulance in the water flowing by the sounder. This messes up the sound wave as it passes through, and the echo returned cannot be interpreted by the gage.
 

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Its all in the Transducer. Regardless of whether you are on plane or not. The depth sounder should work. If it isn't, there is either a problem with the unit itself or the transducer. Stepped hulls have problems due to the nature of the hull. More air under the boat, etc. If yours is a stepped hull and you paid someone to install the transducer, they didn't do it properly. The only time I have ever had false readings was in very muddy, clouded water. If its a transducer mounted to the transome, it is most likely too far towards the outer edge of the boat. Good luck.
 

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Discussion Starter · #7 ·
Thanks Spider,
It is a thru hull transducer and it's factory installed. Has worked for years but now it's acting up.

I guy tried to tell me that it is the hydrofoil creating turbulence. But that is aft of the tranducer so I can't see that being the problem.

Do you know of any way to test it??
 

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Let me clarify that I got a 22 ft boat, and run through LSC chop every weekend 30 - 40 mph. And my just professionallly installed last year Standard Horizon thru hull (god I hated it when they took that hole saw to the bottom of the boat!) that doesn't work above 20 mph isn't performing properly? And the 2 boats before I had would not work properly either?

Now I am interested. what do I need to do to make mine work? Like every other boater, I want to know what my depth is, at all times. At all speeds. I always believed that turbulance thing.

What brand do you use that works for you?
 

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My $.02

if it's through hull they have occasionaly put them in oil/glycerine. This gives the "contact" through the hull. This isn't to say yours is, however perhaps that was how it was done. If that oil were to leak out over time, then there would be the indications you've mentioned. At low speeds the oil would be settled on the bottom, but once on plane or in chop the oil wouldn't be near the transducer and therefore no conductance of the sound through the hull to the transducer.

Again, just my $.02.
 

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When I say thru hull I mean that the sounder is actually sticking out flush with the hull of the boat. I think what your describing with the oil thing is for an in-hull type.
 

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I have Raytheon equipment and my transducer is a through-hull located about 2/3 back from the bow. I get accurate readings on plane (22 - 28 knots). The only false readings I get is when I get in a weedy area.
 

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Discussion Starter · #12 ·
Zesty,
That makes sence!

Do you happen to know if the Uniden sounders use oil or glycol as you described?
 

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Ok, a thru hull is just that. Thru the hull, not mounted on the transom. They are typically a few feet forward of the transom near the lowest point of the bottom of your hull. As for oil in it or what ever I don't know. I have heard that some transducers don't like being painted with antifouling paints. My old 85 Wellcrafts was thru hull and it always worked fine except in muddy/weedy areas. Even painted and on plane at all speeds. Now one other thing, the Wellcrafts top speed was 27MPH or so and the new Maxums top speed is around 33MPH. Over and above that I would believe it is still possible as long as the head unit was rated for it. Its been a long time since I was a Sonarman in the Navy, but from what I remember the frequencys used for depth sounders punches thru anything we have here in the Great Lakes without a problem relating to speed. sound travels, even thru water, a lot faster than any boat.

As for the hydro foil causing interference, that could only happen if it was lifting your boat high enough to put air around the transducer. Any cavatation around the transducer will interfere with it and cause it to fail. It could even cause it to overheat altho that would be unlikely.

Good luck.
 

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Discussion Starter · #14 ·
Ooops Zesty wasn;t the one with the oil fedback that was Edbdboat's $.02.

I just talked to Westmarine, they carry the same Uniden sounder that I have. It does use the oil.

I'll check that out.

Thanks for all of the feed back!!
 

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QUOTE(Spider @ Jul 1 2003, 02:43 PM)I have heard that some transducers don't like being painted with antifouling paints.
I've got a similar problem. Mine will work about half of the time, and only when I'm in water that's 6 feet or better. Isn't it ironic that the only time you need the dam thing is in shallow water, and that's when it doesn't work. My problem started after I painted it with "Transducer Antifouling" paint. I don't know what kind of transducer they're talking about, but I won't use that stuff again. Now I just have to figure out how to get it off. Mineral spirits, or the hull cleaner that you use prior to paint?
 
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