Transducer adjustments??

[rmartinjr4]

I have a Hummingbird Fish/Depth finder on my 17FT PolarKraft with a 50 Rude and it seems that at full throttle I loose my readings. Not sure how it worked at first since I just aquired this boat from a family member, but I did add a hydrofoil to the lower unit. Might this have caused my Hummingbird not to function properly? It is supposed to mark Fish and Depth at up to 70MPH, but at 20knots it goes crazy and produces very false readings. It is mounted at least a foot from the lower unit and appears to be flush to the bottom of the boat. I noticed that at full throttle, the transducer is skidding on top of the water, thus the false readings. Do I need to re-adjust the transducer down a bit? If so, how can I do this? Please, any suggestions would be greatly appreciated.

 

[imported_JD__]

Re: Transducer adjustments??

rmartinjr4,<br />The bracket is designed to "trip" if the transducer strikes a solid object. Reach down, grasp the transducer then pull rearward and upward, it should come unlatched and hinge upward. There should be a couple of screws hidden under the hinged cap. I adjust my 'ducer so its face is running at least 1/2" below the boat's hull. Keeping it in undisturbed, non-turbulent water is the idea.<br />JD

 

[rickdb1boat]

Re: Transducer adjustments??

You will need to lower that transducer a bit so it stays in clean water. If it's at the surface, it cannot read air. Drop it down 1/2"-1" if you can and see how it does. You may need to fabricate your own bracket to get it down low enough. I believe they have the slots in the mount to move it up or down a bit, but I'm sure you have already tried that...<br /><br /> web page

 

[vissertrades]

Re: Transducer adjustments??

Bottom of the transducer surface needs to be slightly below boat bottom and angled slightly, with the front higher (1/8-1/4") than the rear. Mine was flush and not tilted and I had the same issues as you...

 

[Boatist]

Re: Transducer adjustments??

RMartinJr<br />Good advice so far. The transducer needs to point straight down also. So it is not aligned with the bottom of a V hull. As you pick up speed your boat will make a lot of air bubbles if any of these bubbles go under your transducer them it will interfeer with you sending out and getting back a good sound signal. Aluminum boats with lots of rivets sometimes require a kick up Bracket that will put the transducer 3 or four inches below the hull.<br /><br />Can you see fish up to 70 miles per hour??? You did not say what type transducer you have but assume it is a standard 200 Khz 20 degree transducer then not likely you will see any fish at 70MPH. Say you are running up a river 30 feet deep then your transducer will see a 10 foot circle on the bottom. A fish near the bottom should send Back a echo and you should receive it. Now time how long it takes you to go 10 feet at 70 Mph and I think you will find around 1/10 of a second. Now look at you screen and see how many pixel you draw in 1/10 of a second and I think you will know why your not going to see fish at 70 MPH.<br />70 Mph = 369,600 feet in one hour, or 6,160 feet a minute, or 102.7 feet a second so 10 feet takes about 1/10 fo a second.<br /><br />In deep water with a 50khz 45 degree transducer you can see fish at a little higher speed. In general if your not fishing deep to see fish you need to be near trolling speeds.<br /><br />One last thing and I should not say it but the number one complaint of hummingbird owners has been can not see bottom or fish at planeing speeds. I always though it was installation of the transducer but so many had the same problem I know think that maybe the transducer it self creates bubbles.<br /><br />Good Luck and let us know how you make out.

 

[rickdb1boat]

Re: Transducer adjustments??

I have a bird( I know, I know) and they way I adjust the angle of the transducer is to look at the waterline on the hull and see how it sits in the water. Then adjust to a vertical straight down shooting angle from there. I never lose bottom. and like boatist said, I really don't see fish at 30 MPH, nor do I expect to. But I do see the arches at trolling speeds or less and that's all that matters to me. And mostly, I use it to determine stucture for fishing anyway. BTW, I angle mine a bit outward to compensate for the boat sitting lower in the water in the stern.

 

[Capt Joe]

Re: Transducer adjustments??

I have the same problem. It is very disconcerting to be in 1 metre (3 ft) of water in a reef/bar area & suddenly the sounder says you have 120 metres. Definite indication to slow down fast.

 

[Homerr]

Re: Transducer adjustments??

While cruising along one day at the coast, my Lowrance X65 picked up a sea lion one time when I was cruising along a channel. He just popped under the water as I went over, so I knew it must have been him.<br /><br />SCARED the Bejesus out of us! Went from 50 ft. to 5 in a matter of seconds!<br /><br />I never stopped a boat so fast!<br /><br />H.

 

[rmartinjr4]

Re: Transducer adjustments??

Thank you all for the advice! I just returned from a fishing excursion that ended up with me being stranded (so to speak) about five miles from where we were staying on Lake LBJ (Kingsland). Still had problems with my Bird, but bigger problems with the motor. I believe it has seen its better days. I was out there three days on a mini vacation and my boat broke down on me the first day. Presently, it is in the shop, but not sure what to expect. Flooded the plugs pretty bad and it never recovered. Also, the lower unit where the water pump is was leaking both water and gas. It is an 88 Rude handed down to me and depending on the repair cost, I may just have to purchase a new boat. Actually, there is a deal in the works for a G3 1756CC Tunnel (prefer saltwater fishing) so wish me luck. I know that repairs will run quite a bit cheaper ($150-$350)than a new boat, but as I said the boat and motor have seem their better days. I have used it three times since I got it and it has failed me twice. The only good thing that came out of this is that the wife herself was pretty upset and it was her idea for us to get a new one. What a deal, HUH?? Thanks again.

 

[rickdb1boat]

Re: Transducer adjustments??

Something else I noticed, is with a hydrofoil on there, it really shoves that water toward the transducer and causes alot of tubulance that may effect performance. Just something I notice the last time out...