Depth Sounder Dying?

[Roger Long]

My Standard Horizon depth sounder has been one of those items that is so reliable that I just take it for granted, sort of like the hull.

First time out after relaunch yesterday, I looked down and it was showing the double dash display normally seen in water too deep for it to read but I was in less than 20 feet. I first thought it must be some very soft mud where I have seen this in shallow water a few times before. There isn't much of that in Maine though.

On yesterday's sail and this morning the "- -" display showed up at increasing intervals in all water depths. It would go blank for 5 - 10 minutes roughly every half hour to hour. The transducer is one of those glued inside the hull. I tried wiggling all the wires I could reach while my son watched but it never flickered. About half way through today's motoring, it started working normally.

Has anyone seen this kind of behavior? Is it a sign of old age and imminent failure?

This did get me thinking. Even if it resumes and keeps working normally, the depth sounder is the primary navigation instrument in the ICW, far more important than either the compass or the GPS. I think a second unit, probably a transducer that my Garmin chartplotter can read and display would be a good investment. There is a "Depth" box right in the display.

I'll have to do some research and see if the two transducers can work together without confusing each other.

 

[dparilla]

I ran into the same issue with my datamarine sounder last year. I was able to replace the transducer, but in the process I put in a sounder and transducer that are tied into my garmin 3200 series. They worked together just fine, and now I have the original one just forward of the keel and set to depth under keel. The Garmin shoot through transducer is mounted aft under my quarter berth and shows actual depth of the water right on the plotter. Installation of the shoot through was easy.

 

[Benny17441]

My old SH used to do that, just remove the wire leading to the transducer and re-connect again. Not saying for certain that its condition was related to yours but it's worth a try. Threr was a posting on this forum about a company that was repairing these units, check the archives.

 

[RAD]

I too have the original depth sounder and it has a through hull and only after relaunch it would act funny.......so I added a sonar to the Garmin chart plotter and now have both,my original transducer is right under the helm and my thinking was I'd be aground before I knew it heading close to a beach so the new sounder transducer is at the bow

 

[Mick143]

Replaced my ST-50 with a ST-40 using the same transducer. You will have to cut the connection off the new one, beads of sweat will form on your brow. After you splice the new one in, it should work fine. I took my ST-50 apart because it had a clouded screen. It literately went boing and parts flew over the deck, thus I have the ST-40.

 

[SEMIJim]

Our Raymarine ST60+ did that a few weeks ago. It turned out whomever had installed the Airmar in-hull transducer had neglected to install the rubber o-ring around the transducer, so every time Abracadabra heeled, a little bit of the mineral spirits would dribble out of the reservoir. Finally, enough leaked out to make the transducer stop working.

Luckily I had a physically identical transducer for our Garmin chart plotter's sounder that I'd never gotten around to installing. Mopped-out the remaining mineral spirits, measured-in the amount specified by Airmar, put on the o-ring, and we were back in business.

Replacing that o-ring was annoying, tho. Airmar won't sell you anything directly. The only place I could find them, on-line, charges $9, flat rate, for shipping. The o-ring costs $1.40.

Jim

 

[Bob J.]

When you were out of the water put any new bottom paint on?

 

[Roger Long]

When you were out of the water put any new bottom paint on?

Yes, and I was pretty generous with it as well. That thought has occurred to me but the VC17M I use is pretty thin.

I wonder though if it aging or setting up further underwater could explain the improvement over a couple of days.

It will be a while before I know. My engine has just developed potentially mortal symptoms and it's may be quite a while, if ever, that I'm underway again.

 

[Maine Sail]

Roger,

I have an old SH depth gauge in my barn somewhere. It would allow you to isolate it to the display or transducer. It is a SH display that uses a 200kHz ducer...

 

[Roger Long]

Roger,

I have an old SH depth gauge in my barn somewhere.

Thanks but it's a moot point now until I figure out how fuel is getting into my crankcase at the rate of about a quart every 10 hours. It isn't the diaphragm fuel pump.

 

[Bob J.]

My engine has just developed potentially mortal symptoms and it's may be quite a while, if ever, that I'm underway again.

Yea I just read that, sorry to hear about more engine trouble.
That engine held together long enough to get you back home & that's a good thing Roger!

Keep the faith, you'll be underway again.

 

[Roger Long]

I took apart enough interior liner to get at the RCA plug to the depth sounder. It looked tight and clean but I gave it a spray with this stuff that MaineSail told me about last year:

http://www.all-spec.com/products/D5S-6.html

I didn't see a single signal dropout on a sail yesterday.

MaineSail saved my butt, or at least hundreds of dollars, with a quick squirt of this stuff on my radar connector last spring. There should be a can on every boat. Connections that will test and appear just fine for 12 volts often won't carry weaker data signals.

BTW, my engine is fine. Details on my forum.