Humminbird Fishfinder problems

I have a Humminbird 787 fishfinder/GPS I purchased new about a year ago. The unit is not picking up any fish. The unit is working properly in regards to depth, speed, structure, and sonar, everyhting but locating fish. I checked the unit and the fish id is turned on, the sensitivity is turned up. I tried doing a factory reset but with no luck. The way the cables plug in the unit is that they mount in the base and the actual unit "pops on and off" and when you pop it on to the base the the cables fit inside the unit. I thought it might be that the transducer cable was not getting a good connection but would the temp, speed, depth, etc. be working and not the fish id. if that was that was the case.

Thanks for any help. Mike

If it is showing the bottom and structure it should mark fish, if they are there.

I agree you would think that but it is not. The fishfinder in the front of the boat will be reading fish while this one does not. If that is not convincing enough, I can cover alot of water trolling, etc and not the first fish will appear on screen, for about six months now. So either Barren and Nolin lakes do not have any fish and the front fishfinder is lying...or it is messed up. I saw where you can go to humminbird.com and get software updates. I guess I will give that a try. You can change which transducer you want to use and it is set on the dual beam so I don't know what else to try.

Take a fish sized object and dangle it in the sonar beam directly under the Xducer (in the water of course)....

I will give that a try...have you ever done that and saw the object?

You should atleast be able to see a 1 oz fishing weight under the 'ducer....possibly even your jig if the sensitivity is set high enough. AND...you should be able to see that weight move up and down (slowly).

If the 787 has "Restore Factory Defaults" in the menu somewhere...I would try that also...

I have a 778C, and you should be able to take a 1/2 oz sinker and jig in under the transducer. It should show up very easily. I can jig 1/16 and see it with the sensitivity turned up.

Is they sensitivity set high enough?

I did try "restore factory defaults" with no luck. I also had the sensitivity turned up too 100. I am going to put some brush piles out Monday so I will give the jig and sinker a try. I sent an email to humminbird but have not received a response yet. I checked for an software upgrade but could not find one. Thanks for the help.

What are your options for changing the beam cone angle...

It has dual beam and quadra beam options. It came with dual beam transducer. It has option for quadra beam but I do not have quadra beam transducer.

If your dual beam xducer has selectable narrow and wide settings...try the wide setting or the blended (both) setting...

My line of thought here may be that your narrow cone angle setting is just not covering enough water area to easily "see" fish...especially in shallower water...

I will give that a try. I am going to put some brush piles out today so I will check it out and let you know if I have any luck.

Thanks

Be sure and try dangling something in the xducer sonar cone to see if the unit will show it...

and post back your results...

Is this a model 787c or is it a model 787c2 unit? You will have to watch the start up screen to be sure which it is. The 787c software only goes up to the 3.050 version but the 787c2 software goes up to the 4.960 version.

Try these in the order shown:
- Shut the front sonar unit off and see if this makes a difference or not.
- Try updating the software in the unit if it is not already running the latest available version (be sure to restore the menus to the factory defaults before doing so).
- Set the SwitchFire menu to the “Max Mode” setting.
- Test your 787 unit on another boat/Humminbird DualBeam transducer.

Thanks for the helpful info Greg. I told everyone wrong about the model. The unit that is not working properly is a Humminbird 757c. I have a 787 but it is the unit in the front of the boat and it works fine. Thanks again and sorry.

The 757 should have the same software updates available for it as does your 787 unit. Only real difference between these units is the display so you should be able to use the same menu settings (once you have updated both units) are get similar results. If not, try swapping the units around so they are using the other’s transducer and test them again.

Thanks Greg! I will give that a try. I thought this morning that I could swap transducers and see if it is the transducer, but if I understand you I can just swap the actual units from one base to another and that will be doing the same thing just alot easier.

Thanks,
Mike

That’s right Mike, just snap the units on the other’s mount and test away.

You mentioned your front unit is showing fish, but the back unit isn't. You aren't trying to run both at the same time are you? There could be interference between them. Try running only one at a time.

Hello Greg. I think I am going to just order a new transducer and go from there. Will the quadra beam plus transducer work with my 757c?

Yes, the QuadraBeam Plus will work with the 757c unit.

Thanks for the quick reply and all you HELPFUL info.

Mike