Transducer placement

[Scousedeli]

The depth sounder on my searider does not register once the rib is planning, where is the best place to mount a transom mounted transducer for a garmin gps map 298?

Cheers, merry christmas

Lee

[Dirk Diggler]

On the transom

[Scousedeli]

Thanks Dirk for that advise!!! Can anyone narrow it down a bit more than that? Its currently on the mid way point between the tube and engine .

Lee

[9D280]

Where is it in relation to the spray rails?


Memory says that they suggest not putting it immediately astern of any "hull upsets", which from memory includes the spray rails. You get strange things happening with the water at speed - it doesn't come off the transom perfectly straight astern due to the angle of the hull, and I suspect if you have it slightly outboard of a spray rail, you might be parking it in a "hole" that isn't there at lower speeds.

Have you got a pic of it;s current position? (and at risk of asking the obvious, the bit in the water is below the level of your hull?)

[Dirk Diggler]

These are the typical installation instructions you get with most transducers....

Mounting Location
To ensure the best performance, the sensor must be in contact
with aeration-free and turbulence-free water. Mount the sensor on
the transom as close to the centerline (keel) of the boat as
possible. On slower heavier displacement hulls, positioning it
farther from the centerline is acceptable.

Caution
: Do not mount in an area of turbulence or bubbles:
Near water intake or discharge openings;
Behind strakes, struts, fittings, or hull irregularities;
Behind eroding paint (an indication of turbulence).
Caution
: Avoid mounting the sensor where the boat may be
supported during trailering, launching, hauling, or storage.
•
Single drive boat
—Mount on the starboard side at least 75mm
(3") beyond the swing radius of the propeller

[matt h]

i always mounted my transom mounted trans in the hull, around 8 inches in, bond it in with RTV sealant dead centre, (make sure NO AIR bubbles or voids in sealant and pass the cable up through the centre of the lower stainless steel nav light bracket on the floor,,(you will have to drill a hole through big enough for the transponder elec connector) if that makes any sense atall!!

i find with transom mounted units, will break off and look messy if on transom

[Nasher]

Originally Posted by matt h

i always mounted my transom mounted trans in the hull

i find with transom mounted units, will break off and look messy if on transom

Couldn't agree more.

Nasher.

[jyasaki]

Last 2 posts notwithstanding, height of the transducer "face" plays a role as well as location.

On plane, the water will come off the rear of the hull, and begin to equalize to normal sea level. You want to get the transducer face deep enough such that ir rides in clean water, but not so deep enough that it's generating a turbulence pattern of its own. [edit] Should add that the normal starting height is having the face of the transducer just below the hull line. Since it will likely be mounted on the deadrise angle, start with that slope running through the center of the transducer pod.

Angle is not so critical, but should be pretty much parallel with the planing part of the hull. A tad rising or falling (up to maybe 5 degrees?) probably won't make much difference.

Given that it's easier to raise and lower (well, depending on the bracket, I suppose) than relocate the thing, I'd start with that.

Luck;

jky

[Scousedeli]

Thanks for all your replies, I'll see if it works on tuesday.

Lee