Losing bottom contact with RM e97

[Ub2m4]

Since my last post I now realize how little I know. Had recharge do work on our boat. E97 chart plotter with a B60-12 transducer. Some our initial problem was software updates. Did not know we were 7.5 and now up to R17. On smoothe surface or light chop good bottom contact up to 35 mph. On mod cop bottom contact lost 15-20 mpg, but good below 15mph. He also said their was a transducer selection in the menu in the chart plotter. Not sure how to find it. He said could not find B60-12 and was told by tech support to pick any transducer as long as not P48.
How do I proceed? Boat bought used and no manuals or instructions Again thanks for your patience.

[Dave - Raymarine - Moderator]

Hello there,

You should be able to find the B60 transducer selection in the FishFinder application's menu. Please follow the instructions below:

While in the FishFinder application press Menu-> Scroll down and press Setup-> Press Transducer Set-up-> Press Transducer and you will see a list of available transducer selections. From there select B60, if available.

- Dave.

[Ub2m4]

Found B60. Easy when I know what I am looking for. Took boat out, bay waters moderate chop. Same issue, over 20 mph lost bottom contact. Tried 3 diff gains, troll, cruise and fish. Same result. What next. Thank you

[Dave - Raymarine - Moderator]

Hello,

At what depth are you testing this out at?

- Dave

[Ub2m4]

6-7 feet Florida bay off Key Largo.

[Dave - Raymarine - Moderator]

Hello,

There is one more test that could be performed and that is an interference test. Get the vessel up to speed where it loses bottom and note the RPM point. Next, stop the vessel and allow the sonar to find bottom. Once the unit is reading bottom properly, bring the motor up to the same RPM point in neutral and see if you lose bottom. If bottom is lost, then you have an interference problem and will need to get someone on board to find the source. If you do not have the same problem, then your issue is most likely cavitation related. Considering the sonar works properly at up to 35 MPH with smooth water, cavitation seems more likely. When air gets in between the transducer and bottom/objects, it is going to interrupt the sound wave's travel time. This issue is caused by how the transducer has been installed, or from another object before/near the transducer.

- Dave

[Ub2m4]

No interference. But tech did tell me slight lip aroun the transducer. Is this enough to cause this problem and will replacing transducer solve the problem. Dave, 1 last ?, your thoughts on a through hull transducer wired directly to my i50 or even an external mount transducer.
Thanks for all your help

[Chuck - Raymarine - Moderator]

Ub2m4,

Please click here to view a FAQ addressing this subject. Should the vessel not be trailered and be of suitable length, then a fishfinder transducer featuring a high speed fairing block would typically be recommended to support high speed operation. As had been suggested by the technician, the lip of the transducer or any sealant which may have been squeezed out around the transducer's flange may be responsible for such aeration. Should any sealant be visible around the lip of the transducer, then you may want to try removing it to improve performance at speed.

Should the vessel not feature inboard propulsion, then a transom mounted instrument depth transducer may be directly interfaced to the depth transducer terminals of the i50 Depth/Tridata Instrument.Alternatively, should the hull be less than 5/8" thick and not cored, then you may want to consider installation of an in-hull transducer which may be directly interfaced to the depth transducer terminals of the i50 Depth/Tridata Instrument. Please click here to view a FAQ addressing this subject.

[Ub2m4]

Thank you and Dave for walking me through this. Since my last question, I have met 3 different boaters in my marina who loose bottom contact and do no worry about or have added transom transducers. They also have been fishing Florida bay and the back country for decades. Nothing like experience. Thanks again.

[Chuck - Raymarine - Moderator]

You're welcome.