Shoot Thru Transducer placement

[BassnChris]

Any on have a 1999 Triton TR-21 that can tell me where to epoxy a Lowrance PDRT-WBL Transducer so that it will work close to at least 60 mph?

I have tried 3 times but it always stop working at about 35 mph.

 

Thank you

[Way2slow]

Too many variables involved to say if it will or will not work.  A lot of LCD units won't work that fast regardless of where the Xducer, especially if it's on of the older units, they just can't process the signal fast enough,  If it happens to have a flasher mode, sometimes that helps.

If the angle of the Xducer is a little off, it won't work that fast.

If the fiberglass happens to be super think or have micro air bubbles in the layup, it won't work that fast.   Also, small chips or rough a rough surface in the hull in front of or under where it's being mounted can cause turbulence that interferes with the signal.    

If you happen to have a transom mounted Xducer, I would properly mount it to see if it works, and make sure shooting through the hull is the only problem.

If you take some clay or something and make you a water proof pocket that you put water in, then sit the transducer in that with something to hold it down, you can move it around to see if there happens to be a better spot in the hull to shoot through.  The water actually works better than epoxy, so sometimes you can get it working like that, then epoxy it in and it not work as well.

It working at 35mph, I made the assumption you were trying to mount it in the drain sump, but if not, since that's about the only spot it's not double hull, as WRB stated, start there.

 

[WRB]

The TD must be on the flat plane pad surface. The spot is the drain sump surface at the back of the transom.

Tom

[Jig Man]

Since you have tried and had trouble, I suggest that you select a place and weight it down with a sand bag then take it to the lake.  You can move it around until you get it right.

[BassnChris]

I have done that half a dozen times.

I never had any problems with my other boats.

I was hoping to find someone with a boat like mine that could tell me if their's worked and where it is placed.

[Way2slow]

When you were doing your testing, did you have the transducer in a pool of water?  If not, it's not going to read properly.  The face of it has to be on a flat surface with no air or air bubbles under it.  Water is about the best thing to accomplish that with.   That's why when you epoxy it down, you put a whole lot more than needed and push down firmly to minimize the thickness of the layer under it and to push out any air bubbles that might be in it.

Like I said also, a bad layup in the fiberglass under it will cause your problem.  

[BassnChris]

I placed Transducer all over bilge area with sand bags on it. Then flooded bilge enough water to cover transducer.

[BassnChris]

4 hours ago, WRB said:

The TD must be on the flat plane pad surface. The spot is the drain sump surface at the back of the transom.

Tom

I'll buy another Transducer and try that area again. Maybe with clay 'cup' mentioned by Way2Slow.

[Ski213]

Great advice above. Doubt this will help you much. But just in case. Different boat, different transducer setup. It’s a 98 201 stratos. No clue how similar the hulls are. The pics are of the factory installed thru hull not shoot thru, so no glass, thickness or air bubble issues. First pic is the general layout from the back, second is the transducer in relation to it. It’s 14” forward of the drain plug and 3” off the center of the boat. The dead rise (I think that’s the right term) is 9° give or take on my boat. It looks like they cheated the TD a bit but it’s still prob at a 6° angle. When the unit it was attached to worked it would read right up to 60mph. That was the original unit at the console.  Hope it’s of some help. 

[Way2slow]

If you had water in the sump and the XDucer weighted down, you don't need make clay cup.   

As I said in my first post, a number of things can cause your problem.  It could simply be sitting at the wrong angle.  

[WRB]

The Trident has a flat plane pad about 14” wide, the photo doesn’t have a flat plane pad, it’s a slight V.

Tom