'88 228 Seafarer. Running an HDS 12 gen 3 graph. Installing a new Lowrance 3 in 1 Active imaging transducer. Was recommended to install it under the engine bracket (aluminum transom extension) starboard side of the drain plug. Has anyone installed this transducer in this location and what have been your results? Anyone else running this or a similar setup and where do you have the transducer placed? Any info or pics is greatly appreciated.
Lowrance 3 in 1 transducer position "88 Seafarer
- Thread starter Bigedpa
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Sardinia306Canyon
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Do you have single or twin engines, single i guess?
If you have twins then center keel just stbd side of drain plug should work, thats where is my GT51M-TM what is a little bigger thatn the 3in1
Should you have a single outboard then not sure if this position works as it will most likely disturb water flow to prop, even with a bracket.
For single engine you should go stbd 15 inch from prop and not behind any protrusion or mount if backwards on a to fabricate bracket backwards on center keel.
The to make bracket is needed that you can slide the transducer out to remove it when trailering, a common solution here in Italy, iof you are interested in this solution let me know and i will try to find some videos how it works.
I had a GT51M-TM mounted on port side of port engine on the step under the transom of my Venture 34 and it worked very well.
Can you post some photos of your transom and bracket, the solution suggested may work, or not.
Chris
If you have twins then center keel just stbd side of drain plug should work, thats where is my GT51M-TM what is a little bigger thatn the 3in1
Should you have a single outboard then not sure if this position works as it will most likely disturb water flow to prop, even with a bracket.
For single engine you should go stbd 15 inch from prop and not behind any protrusion or mount if backwards on a to fabricate bracket backwards on center keel.
The to make bracket is needed that you can slide the transducer out to remove it when trailering, a common solution here in Italy, iof you are interested in this solution let me know and i will try to find some videos how it works.
I had a GT51M-TM mounted on port side of port engine on the step under the transom of my Venture 34 and it worked very well.
Can you post some photos of your transom and bracket, the solution suggested may work, or not.
Chris
Chris. Thanks for the reply. Sure, any pics or videos would be helpful. I have attached several pics of the stern for reference.
For those reading for information, I spoke to GW customer service. They said mounting the transducer is not an issue under the Grady Drive (engine bracket) as long as the transducer has clean water , no air disturbance, and stays away from the chines. Other info from other sites has suggested a minimum distance from the transducer to the prop of 15". I'm also going to be mounting the transducer to a stern saver board so as to 1, allow for movement and adjustment and 2, avoid drilling more holes into the transom. That's the plan unless Chris is able to provide some pics or videos of their Italian bracket design.
Sardinia306Canyon
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Thanks for the photos, that makes it easier to understand and give hints.
This is how it may look, other systems use a commercially available fairing as below or a kind of bracket with lock mechanism to remove the transducer when trailering.
As you see the transducer is mounted backwards to create space for the cable, so in your Lowrance you need to invert the sides in the settings.
There are better systems as the one below, but owner claims that it works.
My buddy has a removable sled kind one, if you are interested in this solution i may ask him to take photos.
In any case, it's a base with side rails mounted on the keel and a base plate mounted on transducer so transducer and plate slides in keel mounted railed base.
To avoid that water pressure pushes the transducer out of the railed base plate he used a spring loaded ss version similar like this one below to lock transducer in place.
You need a removable transducer only if keel is to near the trailer beam and transducer would not fit in between, if there is enough space between keel, transducer and trailer beam you can install transducer permanently, either as above or using a available bracket as the ones below.
Check if your Lowrance has the function to invert side-scan sides, if not this installation will not work as sides would be inverted!
Ready available 3D Printed Fairing
Ready available Metals bracket for installation below hull
- yes, us a transom saver to be able to move the transducer without drilling many holes
- i would start transducer bracket just stbd side of the drain plug, if you esperience ventilation issues then move transducer more stbd
- yes, general norm is 15" from prop, but i saw it many times that it can works also with less distance to prop
- in case of your boat with bracket it should work as prop sit considerable more back
This is how it may look, other systems use a commercially available fairing as below or a kind of bracket with lock mechanism to remove the transducer when trailering.
As you see the transducer is mounted backwards to create space for the cable, so in your Lowrance you need to invert the sides in the settings.
There are better systems as the one below, but owner claims that it works.
My buddy has a removable sled kind one, if you are interested in this solution i may ask him to take photos.
In any case, it's a base with side rails mounted on the keel and a base plate mounted on transducer so transducer and plate slides in keel mounted railed base.
To avoid that water pressure pushes the transducer out of the railed base plate he used a spring loaded ss version similar like this one below to lock transducer in place.
You need a removable transducer only if keel is to near the trailer beam and transducer would not fit in between, if there is enough space between keel, transducer and trailer beam you can install transducer permanently, either as above or using a available bracket as the ones below.
Check if your Lowrance has the function to invert side-scan sides, if not this installation will not work as sides would be inverted!
Ready available 3D Printed Fairing
Ready available Metals bracket for installation below hull
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Big... it sounds like you might be getting lot's of information from various internet searching that doesn't always apply to your situation. Focus on the installation manual that comes with the unit for the most accurate info.
For example, the "15 inches" statement does not apply in any way to your situation since your engine is on a bracket.
There is no such thing as a "best place". The MAIN thing to look for is where you would have clean water coming across the hull bottom. Other than staying a bit away from the chines, you can really put it anywhere you have clean water.
What this means is that you have to look at YOUR hull to visualize this. Look for obstructions such as strakes, thru-hulls, etc. Other than that, it's not something to overthink - find a clean spot, install it and go boating.
You probably have plenty of room on the port side of the transom, right?
For example, the "15 inches" statement does not apply in any way to your situation since your engine is on a bracket.
There is no such thing as a "best place". The MAIN thing to look for is where you would have clean water coming across the hull bottom. Other than staying a bit away from the chines, you can really put it anywhere you have clean water.
What this means is that you have to look at YOUR hull to visualize this. Look for obstructions such as strakes, thru-hulls, etc. Other than that, it's not something to overthink - find a clean spot, install it and go boating.
You probably have plenty of room on the port side of the transom, right?
Sardinia306Canyon
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You are correct,
however a side-scan transducer should be installed as deep and as much center line so that he can see on both sides.
I had to mount my TM265LH on the port side as there was no good location on stbd side and even there i had no issues because he was on the "wrong" side.
Chris
however a side-scan transducer should be installed as deep and as much center line so that he can see on both sides.
I had to mount my TM265LH on the port side as there was no good location on stbd side and even there i had no issues because he was on the "wrong" side.
Chris
Oh, is that what that transducer that he has is? I guess his installation directions would probably tell him
"Wrong side" - that's funny. It's funny because I KNOW that you are being sarcastic (joking) with that statement!
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Yes, it was sarcastic, however transducers should be installed stbd side of normal rotation lower unit.
I just remembered that my RIB came with a counter rotating LU so i installed the transducer port side wat was correct but who noticed that started to argue till he realised that i had a counter-rotating LU, so position was correct.
OP's 3-1 transducer is considerable shorter than my GT51M-TM and as i wrote, i know many who have it installed center line in front of a single outboard and no problems with prop happen. But it can create problems, so it's a risky location and moving it to another position may be required.
Yes the Lowrance Installing Instruction will know it better and they most likely state, stbd side and not behind and potrusion or center keel if twin engine boat.
I have my longer GT51M-TM "near" the stbd side propeller as stbd side of bilge drain plug and it does not create problems.
In center between twin outboards transom center mounted transducers is always the wrong side as he will get the "bad" upward movement from stbd prop, if props and LU (if not Suzuki AP) are inverted then from port side prop
The reason for the removable sled bracket under the hull is that Italians don't float on the trailer, the get the tier a bit wet and then crank the 10-20 ft rib on the center rollers on the trailer, European trailers rarely have bunks, they mostly have rollers instead.
Most ramps here are shitty ones and when cranking the boat up the transducer under the stern may hit bottom, so they remove it before using a ramp.
Also the transducer on the keel may hit the first roller on the beam what does usually not happen on trailers with bunks.
A search found a installation manual for the Lowrance/Simrad 3-1 to download HERE
Chris
I just remembered that my RIB came with a counter rotating LU so i installed the transducer port side wat was correct but who noticed that started to argue till he realised that i had a counter-rotating LU, so position was correct.
OP's 3-1 transducer is considerable shorter than my GT51M-TM and as i wrote, i know many who have it installed center line in front of a single outboard and no problems with prop happen. But it can create problems, so it's a risky location and moving it to another position may be required.
Yes the Lowrance Installing Instruction will know it better and they most likely state, stbd side and not behind and potrusion or center keel if twin engine boat.
I have my longer GT51M-TM "near" the stbd side propeller as stbd side of bilge drain plug and it does not create problems.
In center between twin outboards transom center mounted transducers is always the wrong side as he will get the "bad" upward movement from stbd prop, if props and LU (if not Suzuki AP) are inverted then from port side prop
The reason for the removable sled bracket under the hull is that Italians don't float on the trailer, the get the tier a bit wet and then crank the 10-20 ft rib on the center rollers on the trailer, European trailers rarely have bunks, they mostly have rollers instead.
Most ramps here are shitty ones and when cranking the boat up the transducer under the stern may hit bottom, so they remove it before using a ramp.
Also the transducer on the keel may hit the first roller on the beam what does usually not happen on trailers with bunks.
A search found a installation manual for the Lowrance/Simrad 3-1 to download HERE
Chris
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Reel-Magic
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I ran my old Lowrance 3-1 there for years and it worked ok. Not bad inshore sitting still. Once you hit 10 knots you just read all the aeration. Not saying anything bad I used it for years but I did upgrade to a B75HW thru hull this year and I wish I did it years ago it’s much better. Comes in 20° as well made for an easy install.
Sardinia306Canyon
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Where is there?
A correctly installed skimmer type transom mounted transducer will read up to 30 knots, the GT51M-TM on my Venture 34 was reading perfectly up to 30 knots and in side-scan down to about 180ft.
Correctly installed means
- correct transducer depth below hull
- correct angle regarding water flow
- no protrusions in front of transducer
- not near strakes, chines, trim tabs or similar devices
The point for success or fail is width of strake (must be wider than transducer) and on the lowest strake to get less aerated water coming from bow flowing along the hull.
Most errors in installation of TM transducers is transducer too deep and creating turbulence by the bracket hit by water flow and wrong inclination regarding water surface. Most skimmer type transducers should skim the surface and protrude only a few mils below hull and be parallel to water surface when boat is at a given speed.
As boats - some more and some less - change level when going 0 knots - 8 knots - 14 knots - planing speed a compromise has to be found regarding reading quality.
- transducers rear more up for best side-scan readings at 3-6 knots, but transducer may read not well at planning speed as rear is too high
- transducers surface parallel to water surface at planing speed will give best high speed readings but bad side-scan readings
- somewhere in the middle of transducers rear up to get not perfect readings for side-scan and traditional view at any speed
If no side-scan is desired a flat transducer like the B75/B164/B175 gives better readings at deeper water, but the hull must be drilled and on some hulls and/or positions they don't read well at speed as they are very near the hull and areated water can disturb the reading at speed.
Chris
Stbd side.. yes, I completely agree when an outdrive/outboard is mounted direct to the transom. However in this case, the OB is mounted on a bracket so it's quite a distance away (forward) from the prop disturbance. So in this case, the port side is just as good.
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Reel-Magic
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Where the manufacturer said to install it, under the bracket. I thought the OP was talking about a Lowrance 3-1 Transducer on a Seafarer, not a Garmin on Venture 34 sorry.
Sardinia306Canyon
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Thats what i wrote in my reply #5, under the bracket stbd side of drain plug, i(f this side is occupied, then port side of drain plug as Dennis1 correctly mentioned.
The Lowrance 3-1 and the GT51M-TM are very similar (except length) transducers and the Venture 34 has a built-in bracket or stepped transom, but obviously is longer and wider what does not really matter for transducer performance or aeration problems..
My GT51M-TM on my 306 Canyon does read well at 25 knots and i am still tweaking inclination it to get better in side-scan and reading at speed.
Chris
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