Advice on mounting tranducer..

[rauch0812]

We are about to mount our transducer on the back of the boat and a friend recommend mounting one of those white transducer mounting plates first. So here are my questions...

1. Does anyone else recommend this? If I mount one it will have to be horizontally and the screw holes will still have to be under the waterline just because of the shape of our boat above the water line.

2. Does it have to be this "white" type of board? The bottom of our boat is black and I think this white hunk of plastic isn't going to look great. Granted, you won't see it when the boat is in the water but I'll know it looks awful while were trailering down the road...

3. Above the water line we'll have to make a hole for the cord, we're going to try to tuck it up under the swim deck the best we can. But why do they put this big plug on the end of the cord (that plugs into the back of the hds unit) but the cord is only half the diameter, meaning we have to make a big hole and the cord will only fill half of it... Any advice on making this look decent?

Any other advice at all before we do this? It feels wrong to add all of these holes to the boat and add blocks and cords and holes that look crappy. I'd love direction on this!

Thanks,
Desera

 

[BaileysBoat]

Re: Advice on mounting tranducer..

Wouldn't mind a picture. What kind of boat.

Mounting a transducer is not an exact science. Takes some experimentation to find the correct mounting point.

I made an adjustable bracket out of aluminum for mine.

This can cover the wiring.

http://www.iboats.com/Seasense-Mini...51880194--**********.538095181--view_id.56430

 

[NoThanksDad]

Re: Advice on mounting tranducer..

Desera,

I have never used the mounting plate your talking about, so I'll leave that response to someone who knows.

As for the hole you need to drill for the electrical wire (above waterline). Assuming you have a wood core, when you drill the hole (only big enough for the plug to slip through), I would coat the now exposed end grain with epoxy to make sure you don't get any water wicking into your transom at any point in the future.

Once that's dry, I sealed the hole in my boat with 3M Fast cure 4200 (or 5200) Polyurethane Adhesive/Sealant. While the 3M sealant is still wet (and a little messy) I put a stainless steel clam shell vent over the hole. (this attaches to the transom with 3 small shallow screws.)

Once you put the clam shell on put more of the sealant up under the clam shell to guarantee that the hole is completely sealed up. IMO this clam shell makes the hole look a lot better b/c you can't see the hole and the SS makes it look factory installed.

You'll probably need to put two or three small cable clamps (one small screw each) to hold the line below the water line tight to the transom. (You won't want that flopping around).

I would put a small amount of 4200 in and on each of the small screw holes (clamps and clam shell) to seal each of those holes.

It sounds like alot, but it's really not that bad.

Below are a few links that you may find helpful.

Good luck

3M 4200 link
http://www.westmarine.com/webapp/wc...001&storeId=11151&partNumber=593154&langId=-1

Stainless steel "clam shell vent" link:
http://www.westmarine.com/webapp/wc...toreNum=10114&subdeptNum=10665&classNum=10666

Cable Clamp link
http://www.westmarine.com/webapp/wc...toreNum=10109&subdeptNum=10611&classNum=10612

 

[bowman316]

Re: Advice on mounting tranducer..

let me guess, it is a lowrance fish finder?
i just installed a thru hull transducer on my boat.
i had to drill a half inch hole just to run the wire thru, with the big plug on the end.

seems dumb to me too.

just make sure u mount the transducer where it will still be in the water when on plane, and A few feet away from the motor

 

[rauch0812]

Re: Advice on mounting tranducer..

I don't have a picture of the back of my boat, so I'll get one up tonight. Hopefully you guys can point me to where I should mount it.

Thanks for the detailed directions - looks like I'll have to send hubby off to the store before we get started.

And yes... it is the Lowrance. I was really hoping someone would post that we're crazy and the end plug comes off or something. It is what it is.

So nobody here used the mounting plate?

http://www.basspro.com/webapp/wcs/s...01_9153_250003000_250000000_250003000_250-3-0

http://www.bargainoutfitters.com/ne...ducer-plates-or-mounting-boards.aspx?a=298878

I gather up the hardware and 4200 and get a picture of the boat on here tonight.

Thanks guys!
Desera

'98 Larson 206 Lxi BR

 

[John_S]

Re: Advice on mounting tranducer..

We are about to mount our transducer on the back of the boat and a friend recommend mounting one of those white transducer mounting plates first. So here are my questions...

1. Does anyone else recommend this? If I mount one it will have to be horizontally and the screw holes will still have to be under the waterline just because of the shape of our boat above the water line.

Yes, I highly recommend using the board. If you mount direct, and do not do enough pre-testing, you could end up with many more holes below the waterline. Use 5200 to seal the mounting screws. Make sure the plate follows along the bottom of your boat. Do not make it horizontal, unless you have a flat-bottom boat.

2. Does it have to be this "white" type of board? The bottom of our boat is black and I think this white hunk of plastic isn't going to look great. Granted, you won't see it when the boat is in the water but I'll know it looks awful while were trailering down the road...

No, but all the ones I've seen are white. I made my own from some left over king starboard. It is white, and doesn't botther me with a green hull. I believe king starboard can be painted or comes in other colors. A little pricy if you don't have scraps laying around.

3. Above the water line we'll have to make a hole for the cord, we're going to try to tuck it up under the swim deck the best we can. But why do they put this big plug on the end of the cord (that plugs into the back of the hds unit) but the cord is only half the diameter, meaning we have to make a big hole and the cord will only fill half of it... Any advice on making this look decent?

Yep, as far as I know, all the brands are like that. I don't know about Lowrance, but HB provides some rectangular caps that can be mounted over the hole. Two more screw holes, though.

 

[Damifudo]

Re: Advice on mounting tranducer..

I just mounted mine up this week, One make sure your cord is long enough first. I got mine all mounted and found my cord about 5 feet short of my head unit. Uggg. I had to purchase a 25 dollar extension cord. I pit the bullet and drilled into my new transom but sealed the holes very well with 4200.

I had to drill a 5/8 inch hole above the water line for the stupid small wire just to get the connector through because it is molded on. How stupied is that? The dang drill bit cost 17 dollars. I couldnt use a paddle bit because there was already a hole there from an old transducer that was drill smaller than the new unit. I used the clam shell and calked the hole up good with 4200.

I know how you feel drilling below the water line always feels so wrong.

Good Luck.

 

[rauch0812]

Re: Advice on mounting tranducer..

Do think I could hit the mounting plate with my extra bottom paint to make it black?
http://www.bargainoutfitters.com/net....aspx?a=298878
Just curious if it would stick...


Do I order the 1st or the 2nd one? (Handy-woman I am NOT)...
Stainless steel "clam shell vent" link:
http://www.westmarine.com/webapp/wcs...classNum=10666

 

[dingbat]

Re: Advice on mounting tranducer..

Do think I could hit the mounting plate with my extra bottom paint to make it black?
http://www.bargainoutfitters.com/net....aspx?a=298878
Just curious if it would stick...

No, it will not stick

Do I order the 1st or the 2nd one? (Handy-woman I am NOT)...
Stainless steel "clam shell vent" link:
http://www.westmarine.com/webapp/wcs...classNum=10666

As you can see in the picture I ran my cable up and into the cable boot.

If you must go thru the transom then I like these a lot more than a clam shell.

http://www.westmarine.com/webapp/wc...toreNum=10109&subdeptNum=10611&classNum=10612

http://www.westmarine.com/webapp/wc...toreNum=10103&subdeptNum=10278&classNum=11106

 

[NoThanksDad]

Re: Advice on mounting tranducer..

Do think I could hit the mounting plate with my extra bottom paint to make it black?
http://www.bargainoutfitters.com/net....aspx?a=298878
Just curious if it would stick...

Agreed the paint won't stick.

Do I order the 1st or the 2nd one? (Handy-woman I am NOT)...
Stainless steel "clam shell vent" link:
http://www.westmarine.com/webapp/wcs...classNum=10666

I have "A" on my boat (1st one). The one's recomended by dingbat look great too. Regardless of your choice, if you "have to" drill, I would still epoxy the exposed end grain prior to filling the hole with 3M sealant.

 

[Billdc]

Re: Advice on mounting tranducer..

what lowrance unit do you have? I think I read that you tried it in the bilge and it didn't work, How did you mount it in there. Could you just upgrade the transducer to one that would shoot thur the hull?

 

[Blue Crabber]

Re: Advice on mounting tranducer..

what lowrance unit do you have? I think I read that you tried it in the bilge and it didn't work, How did you mount it in there. Could you just upgrade the transducer to one that would shoot thur the hull?

I would absolutely be looking into this idea if you don't like the thought of drilling holes through your boat.

You also need to be careful how you mount the transduced to the inside of the bilge, you can't have any air bubbles between the transducer and the fiberglass.

Let us know how you make out.

 

[bowman316]

Re: Advice on mounting tranducer..

when testing a thru hull transducer, it needs to be covered in water to work, unless it is already epoxied down

 

[rauch0812]

Re: Advice on mounting tranducer..

We epoxied it down with stuff it recommended in the Lowrance book. LE something or other. I even called Lowrance and they said I had to mount it outside of the boat, he said the thru-hull instructions are more for a fishing boat with trolling motor or something of that sort. He said just mount it outside, that's how it's used best. I went online and ordered all of the stuff. I found the transducer plate in gray, nylon clamps in black, the black wire cap, clam shell (just got both so we can decide later) and the 4200. We're just gonna do it!

http://s853.photobucket.com/albums/ab98/rauch0812/?action=view&current=P1010324-Copy.jpg
Tried to add pictures above... hope it worked.
(Ignore the shiney silver prop - that's the result of running aground in the Sass....)

 

[rauch0812]

Re: Advice on mounting tranducer..

More questions...

I purchased the transducer mounting plate (material is polymer or something) to mount to the bottom edge of the boat, but apparently, you can not access the other side (inside the boat). So - bolting it on is not an option... any thoughts?

Has anyone tried mounting the board with 4200, 5200, JB Weld... without any screws under the water line?

 

[John_S]

Re: Advice on mounting tranducer..

More questions...

I purchased the transducer mounting plate (material is polymer or something) to mount to the bottom edge of the boat, but apparently, you can not access the other side (inside the boat). So - bolting it on is not an option... any thoughts?

Has anyone tried mounting the board with 4200, 5200, JB Weld... without any screws under the water line?

Should not require bolt through. Screws should work, just like if you were mounting the transducer by itself.

I haven't tried just glueing it in place. It will hold for awhile, but the question is will it ever come free? If it does, the board and transducer will be gone. Cable will just snap.

 

[mikphilips]

Re: Advice on mounting tranducer..

Several thoughts:

1. Choose best transducer type.
-Transom surface mount (as you are discussing); shows you the bottom detail that you just passed.
-Inside hull surface mount; mounted about 2/3 boat length back from bow to keep in undisturbed water, shows you the bottom detail several feet forward from transom mount / inline with trans, tricky to mount (see previous posts) must be shooting STRAIGHT DOWN, you may have to use a beveled fairing block (spacer that offsets slope of hull at mounting location to allow level base for mounting transducer).
-Outside hull (true thru-hull mount); transducer actually sits in the water surface mounted to hull, shows bottom detail in line with transducer, best image since it is not shooting thru your fiberglass hull and mounting block, etc., you drill one big hole to allow threaded hollow mounting tube to pass thru (wiring is inside tube), epoxy the newly exposed fiberglass inside the hole and bed the trans fully in 5200, once again, the trans must point STRAIGHT DOWN or you will see a distorted image on your display, this often requires a fairing block on the outside AND inside the hull so the tightening bolt on the threaded mounting tube tightens square to a surface, 5200 everywhere (it will be destructive to the hull to remove it later, but it provides the best sealant against water leaks below the waterline).

2. Mount the transducer in clear water; run your boat before mounting trans, if choosing transom mount, look for water (at planing speeds) behind transom that is free of turbulence (bubbles), you want clear water for best operation, look for a spot at least 2ft to the side of the propeller, you want to mount the trans pointing STRAIGHT DOWN with the bottom face of the trans approx 1/4" below the adjacent surface of the hull (measure at centerline of trans, since the trans will likely be angled compared to the sloping deadrise of most hulls at the transom), once again the goal is to place the trans in clear water, this will also give you a truer speed reading if the trans is equipped with a paddle wheel for measuring speed thru water, most mounting blocks for trans allow some up and down adjustment, mount initially at center point of adjustment range for best future adjustability, if you lose your bottom image while on plane, try adjusting your trans deeper into the water, keep adjusting height until best results appear on display.

3. Measure the distance from the bottom of the trans to the bottom of the prop blades, enter this distance into your depth sounder unit as the Keel or Prop Offset, on many units this will allow you to set an alarm if water level ever gets shallower than prop needs before dragging, if you don't set this adjustment, simply use your measurement to know how much water you need to keep prop off bottom, if you tilt the prop out of the water during trolling or drifting then no concern, but you will still want to watch the depth reading as you motor into a shallow area.

4. Check for leaks; check your bilge at the transom for water during the first few runs, I'm on my third boat and yet to have a completely dry bilge, but a major leak and water flow signals the need for a problematic do-over, so use plenty of 5200 and seal up all your holes the first time, if you can run the wires up the face of the transom you will avoid an additional hole below water line, use heat shrink tubing to protect the wires where exposed and use cable clamps to hold wire snug to surface of transom.

Doing it right the first time is always the easiest way to go.
Mike