Through Hull Transducer location on Freedom 275

[jcamp4]

Has anyone installed a Airmar B60 on a Freedom or Tournament 275 and if so where, and how does it perform at higher speeds?

 

[Grouper Duper]

Just had one put in my 263 Chase, which is the same hull as a 273 Chase and maybe the same as yours?

I already had a transducer (that I wanted to keep) and a livewell pickup on each side of the keel (about 1 to 1.5 feet off the keel), so they mounted the new one further out on the port side (maybe 2.5 to 3 feet off the keel). It held bottom only to about 15 knots, and I wasn't happy. I had them move the livewell pickup two feet further aft, and put the new ducer where it was (plus repair the new hole they put in the boat :bang ). Now it holds bottom solidly to 40 knots!

So, keep it close to the keel! You can't put it REAL close to the keel because the hull "rounds out" at the bottom, and you need a flat surface for the flush-mount ducer.

Good luck!

 

[jcamp4]

Thanks for the reply!

My hull is the same as the new fisherman 273 which I think is the same as the 273 Chase.

They mounted mine about 18" off the center on the starboard side about 5' from the transom in the forward rigging compartment.
I too have a livewell p/u to starboard and a washdown p/u to port each about 4" off the center. My b60 is about 14" from the starboard livewell p/u and about 2" aft of it. Mine reads only to about 15mph and will kick in at high speeds on a sharp port or starboard turn.

SO you are saying that your livewell p/u was causing the problem - right?
DO you have any suggestions for my situation?

 

[Grouper Duper]

I think mine was just too far outboard from the keel, and was picking up some bubbles from the strake up near the bow. None of us wanted to believe they would hold the hull so far back, but there was nothing else in the way. You MIGHT get some interference from the livewell pickup since it sounds like it's beside but slightly in front of the ducer (those pickups make a LOT of turbulence). We moved it inboard (sounds like near where yours is now) and moved the livewell pickup behind it and all is well. You can probably get the livewell pickup moved back and the old hole repaired for a couple hundred; might be worth it.

Here's another thought. Before we cut/patched more holes in the hull, we tried holding an old transducer at different locations inside the hull while running at speed (tricky operation for the guy holding the ducer down there!). KY jelly (believe it or not!) worked great for sealing it to the hull during the tests, and it definitely showed us where there was interference under the hull and where there was not.

 

[ocnslr]

My b60 is about 14" from the starboard livewell p/u and about 2" aft of it.

That's the problem. The water aft of the pickups is aerated due to the normal formation of bubbles in the turbulent low-pressure area downstream of the projection.

Those two pickups create enough 'bad water' to cause excessive prop slip when you have a single engine on that hull. I know from 465hrs with a single 250HP engine before we repowered in 2005.

I use an Airmar M256 and shoot through the hull forward, under the cabin sole. I can track at ALL speeds, and have tracked bottom in 3400-ft crossing the Norfolk Canyon. Lowrance LCX-112C with the Lowrance broadband unit.

Brian

 

[bayrat]

Agree with ocnslr...put in a shoot thru the hull transducer from airmar (they make several models). Aside from not putting anymore holes in your hull, its been my experience that they work better than both transom or thru hull transducers as far as depth readings at speed. In the past ,I even used to put my transom mount ducers inside the hull with really good results. The new hockey puck transducers with angle for deadrise are so much better now.