Topic: 1198cSI Losing 2D and Downscan for Unexplained Reason

[wlkinser]

I have a Skeeter with 898cSI on bow and 1198cSI with Y splitter to a thru the hull transducer and a Tranducer Shield & Saver for the SI transducer mounted on the jackplate.  Both are ethernet connected.  Installation was researched and is "as recommended", and worked well until recently.  Began to notice losing 2d when running, but would return when back at idle.  Now, losing both 2D and Downscan.  Works OK when starting up and at idle, but then loses bottom.  Digital readout switches to 2.4 ft. and both 2D and Downscan grids switch to 10 ft.  The 2D shows colors and the Downscan seems to show image, but doesn"t show bottom.  SideScan works.

Just updated from 5.7 to 6.64.  No help.  When I switch to the bow transducer using Accessories tab, works OK.  Also. if I Power Off for a minute and Power back ON, it begins to work again, but then after a few minutes, even if not running, it drops back to 2.4 ft. readout and a 10 ft grid for 2D and Downscan.  I just idled around and Powered Off/ Back On when this happened and it would pick back up for a few minutes showing good images and then for no apparent reason, drop the image back to a 10 ft grid.  Happened multiple times.

Very frustrating!  Any ideas?

[Humminbird_Greg]

Welcome to the Humminbird Side Imaging Forums wlkinser.

So it is losing the 2D sonar even when idling now, correct?
Try moving your 898 unit to the console to test the transducers and to make sure it is not something with the 1198 unit.

If the 898 works okay, move the 1198 back to the console and try disconnecting the AS-Si-DB-Y cable and plugging the thru the hull transducer directly into the 1198 unit.  Test it to see if anything has changed or not.  If it works better; you have an intermittent AS-Si-DB-Y cable.  If it still does not work any better; the thru the hull transducer may be failing or the mounting of the transducer may be failing.  Now by “thru the hull” transducer I am assuming that you are meaning that the transducer is mounted inside-the-hull and shooting its sonar signal through the hull of the boat.  With that assumption: try pouring enough water into the bilge area of your boat to cover the transducer.  You may have to temporarily disable the auto bilge pump if you have one for this (remember to reactivate it after all testing is done!).  Test it again to see if it works better or not.  If it does try removing and remounting the transducer.  If it doesn’t, try removing and testing the transducer by holding it over the side of the boat in the water.  If it reads good you can re-install it back into the boat.  Otherwise replace the transducer.

[wlkinser]

Thanks Greg, but let me ask a really stupid question.  How do I move the 898 to the console?  The connector plug set-up is completely different.  Since they are Ethernet connected, can I just leave the 898 connected at the bow and just have it read the console transducers by changing the Assessories set-up?  If not, how do I connect the 898 to the 1198 connector block?

Also,  I understand your comments about the thru the hull transducer, but I thought the DI came off the SI transducer.  I am losing both 2D and DI at the same time, and I can Power Off and Power back On and they both will start back and run for a few minutes and then appear to lose the bottom contact and shift to reading 10ft.  Does the thru the hull have any effect on the DI? If not, it makes me suspect there might be a problem with the 1198 unit.

Your insights and help are appreciated.

[Humminbird_Greg]

wlkinser,
Excellent questions (not stupid ones) so I hope that my answers are just as informative:

You will have to take the cable connectors out of the connector collector and just plug them up by hand for the test.  Physically connecting the 898 to the transducers to test them makes sure that you are using the transmitter and receiver from a different unit to test them with and not just processing the digital data from the transducers.  If there were a problem with the receiver in the 1198 unit it could still show up on an Ethernet connected unit.  Direct connecting the test unit to the transducers eliminates this possibility.

The Di sonar does come from the Si sonar but the DI sonar (and Si sonar to a lesser extent) relies on data from the 2D sonar to read correctly.  The depth range scale shown for the Di sonar is tied to the same for the 2D sonar.  So when using the depth range scale in the automatic mode; when the 2D sonar starts reading 2.4 feet it changes the depth range to its shallowest setting which is 10 feet.  This also changes the depth range for the Di sonar which puts the bottom reading off the area of the water column being shown.  If you were to manually set the Lower Range menu to say 30 feet when in 25 feet of water, the digital depth may show 2.4 feet but the unit would be displaying 2D and Di sonar readings down to 30 feet.

[wlkinser]

Great explanation!  Perfectly clear and I now understand how it all works.  I feel stupid, though, after looking closer at the connector ( I did not do the install), and seeing how each cable is separate with it's own pin orientation.  I thought that might be the case, but never examined them that closely. Duh! Anyway, I just swapped the 898 to the console and got the same result, so it appears more likely that it is a problem with the Y cable or the 2D transducer.  This is what I originally suspected, but when I lost DI, I was confused.  Your explanation of the relationship between 2D and DI really helped.  Thanks!

 I have read you on this and other sites, and you are a real asset to them all.  We Users love this technology, but it is so sophisticated that we sometimes get lost in understanding how it works and how to fix problems.  It's great that people like you are willing to help us troubleshoot these problems.  Wayne P. in Virginia is another great resource.  Thanks to you both!

I will follow your suggestions on diagnosing the 2D transducer/Y cable operation.  Given that it has progressively gotten worse, I now suspect that the transducer has come lose or is going bad.  Unfortunately, I won't be able to troubleshoot it until late next week, but I will let you know what I find.

Thanks for all your help!

[Humminbird_Greg]

Glad I could help wlkinser.
Let us know how it turns out.

[wlkinser]

Finally got back on the water to finish troubleshooting.  Put 1198 back on console and plugged side imaging and thru the hull transducers directly into 1198 ( bypassing the Y cable).  Sidescan transducer gave all 3 images, until put boat on plane and transducer, which is mounted on jack plate, came out of water.  Once slowed and back to idle, all 3 returned, as expected.  Then, unplugged side imaging and plugged in thru the hull transducer.  Got good 2D image for a few minutes, then lost bottom and went to 2.4 ft.  Powered off/back on, worked again for a minute, then went to 2.4 ft.

Conclusion is Y cable is OK, but thru the hull transducer is bad.  Checked to see if it was loose, but mount still looks good.  Did not do the "water test".  Ordered new transducer and will install next week.  Hopefully, will correct problem.

I haven't epoxied a transducer in a while.  Any advice/ special precautions?  What's the best way to clean/prep. spot and avoid air bubbles?

Thanks!

[Humminbird_Greg]

Epoxying tips:
First and biggest tip is to do the on-water testing to make sure that the mounting area will work!
Make sure the weather is hot enough for the epoxy.  Do not use below 60* F.  Allow 24 hours above 77*F and 48 if between 60*F and 77*F.  I see you are next door in Georgia so this should not be a problem in August!
Prep the location by sanding out any coating paint – you want to epoxy to the fiberglass.  You are not looking for baby smooth here so just use down to a 400 grit paper if even that low.
Remove any liquids, dust and debris from the area (make sure the inside of the hull is dry).
Wash the transducer in a degreasing dishwashing liquid, dry it and lightly sand the bottom with some 400 grit sandpaper.  This will give the epoxy a better surface to adhere to.
Mix the epoxy in the container provided.
Twist the transducer back and forth while pressing down during the installation. This will help force out air bubbles and thin the epoxy (which is what you want).  Don’t worry, there will be enough epoxy left to hold the transducer in place.
Place a weight on the transducer so that it will not move while the epoxy cures.  A plastic bag full of sand/dirt or pea-gravel works good for this.
Be patient and allow the epoxy to cure before moving the boat.

[wlkinser]

Final Report:

Success!  Replaced the dual beam transducer ( thru the hull for 2D sonar while running).  Followed Greg's tips and everything works great.  It's amazing what you can do on the Internet these days.  For an old fisherman (64 yrs), it's pretty cool.  Never called Humminbird.  Posted on this forum and got great advice to diagnose the problem.  Ordered the transducer on Amazon.  Received it in 3 days...no shipping or sale tax.  Installed it using the above instructions, and back in business.  I used to be a Lowrance man, but with support like this, I am a Humminbird fan now.

Thanks, Greg!