Lowrance Transducer help

[Lancerdad34]

I just got and installed a Lowrance Hook2 7. It reads OK and slow speeds but not when I plane out. I tried using the same location from the transducer I replaced but it look like I will have to move it. I added a couple of photos and am looking for suggestions.

Thanks,

Brian in MI

 

[GA_Boater]

Need a pic from the side. It may be a little high and a transducer only works on plane if it skims the water or is in the water.

 

[TunaFish389]

Yeah that veiw is deceiving, I see it as too low. You can always look to see where its at under way.. It should skim the water but still be able to see the top. Also angle should be slightly higher away from boat, the way water naturally travels after leaving hull.

 

[dingbat]

From that picture....
1. The transducer is too low. The bottom of the hull should intersect the center line of the transducer

2. It doesn’t look level (port-starboard)

3. the transducer should be level front to back, should be a little high in the rear if anything rear

 

[Lancerdad34]

Thanks for all the replies! I picked up one of those transducer mounting boards so if I have to drill I do not have to drill any more holes in the transom.

Brian

 

[dingbat]

Thanks for all the replies! I picked up one of those transducer mounting boards so if I have to drill I do not have to drill any more holes in the transom.

Brian

The worn bottom paint from the bunk isn't doing you any favors....

How much bow rise do you have the boat is planing?

Pretty typical for a boat to run bow high 3-7 degrees when on plane. Need to compensate for that angle if you want to keep the sensor parallel to the bottom while on plane.

Being 3-7 degree off plane doesn't sound like much until you consider the error at 250 feet deep

 

[Lancerdad34]

I raised it up it did look like it was a bit too low before. Going fishing in the AM so I will find out then and let you know.

Thanks again,

Brian

 

[dingbat]

I raised it up it did look like it was a bit too low before. Going fishing in the AM so I will find out then and let you know.

Thanks again,

Brian

Still looks way out of level in that picture.

Face of the transducer should be parallel with the ground, not the bottom of the boat

 

[Fed]

Clean the bottom of the boat in front of the transducer if it needs it.
Clean the transducer bottom to a shiny smooth surface.
Lower the transducer to below the bottom of the hull.
Lower the trailing edge of the transducer a few degrees below parallel to the hull.
(You may be limited by the transducer not being infinitely adjustable but you need the trailing edge lower than the leading edge)

This will read up to 40 MPH.

 

[Lancerdad34]

Fed thanks for the advice. It is a new transducer so it is clean. I followed your advice and changed it to what you suggested and I still was losing the bottom at high speed. I have the boat in the well so the only adjustment I can make right now it to raise up the trailing edge and see if that helps. Other than that I will have to wait until I pull it out again on July 8th. I will let all of you know.

Thanks,
Brian

 

[cptbill]

What make of boat is it on? I ask that because the Lowrance unit on my Larson would do the same thing because of the delta conic hull(stepped hull) nothing but bubbles back there when on plane

 

[Fed]

Bubbles are indeed the killer, mounting closer to the keel where there are less bubbles would help.

 

[Lancerdad34]

Bayliner Classic 2450. The transducer is in the same spot where my hook 7 hdi was and that worked fine.

 

[TunaFish389]

Raising up the back end of the transducer help? It shouldn't be digging in the water, just skimming.

 

[Fed]

Take pictures of each side holding a straight edge like in post #9 otherwise it's too much guesswork.

 

[Lancerdad34]

I reached down there yesterday to click it back up but have not been out yet to try. Will let you know.

Thanks Again!

Brian

 

[dingbat]

Raising up the back end of the transducer help? It shouldn't be digging in the water, just skimming.

Transducers perform best when perpendicular to the bottom.

Keeping this in mind, boats don’t plane level with the surface. Most run nose up.

Radar mounts are slightly angled to keep the dome level with the horizontal when the boat is on plane. The same holds true for transducers.

When it comes to mounting transducers, every boat is different.

 

[TunaFish389]

I disagree, it runs best perpendicular to water flow which comes angled upward once leaving the hull.

 

[dingbat]

I disagree, it runs best perpendicular to water flow which comes angled upward once leaving the hull.

Thought we where measuring death? Doesn’t that require the transducer be pointed at the bottom?

 

[Lancerdad34]

Thanks again for all the interest and replies on this! I took it out for a quick spin today and it read bottom much better! I think I will leave it right where it is for now.