drilling hole for transducer cable. need help

[extremez]

i'm going to replace my shoot through with a transom mount. lowrance says i need to drill a 1" hole for the connector. the cable is alot thinner. is there some sort of through hull fitting that i should be looking for.

 

[no1satguy]

Re: drilling hole for transducer cable. need help

I a thinking of doing that too but maybe the cable is thinner but the connector is about half inch or more. Can we just cut the cable and connect it again after inserting in the hole?

 

[NelsonQ]

Re: drilling hole for transducer cable. need help

Guys

Just been down that road and I know the feeling of having the instructions in one hand and the other on a drill with a 1" bit spinning away but as you've stated, its the only way to get it and the connector through.

I opted for the larger hole and used 3M Marine sealant and it worked great to seal the hole.

I'm not sure what's in that cable but if you cut it, you'll need to reconnect and use something to prevent corrosion on the connection and a waterproof seal on the cable joint (heat shrink tubing works fairly well) However, at btw $50-75 for a new transducer, hell of a costly experiment if it doesn't work.

That's why I opted for the hole.

Other option (I don't know Lowrance products) is an in hull transducer. If you go that route, make sure you use a slow cure epoxy to adhere it or you'll get small bubbles that will give you poor readings. They work quite well and require no drilling. Only downside is you lose the temperature sensor component built in to the transom mount transducer.

Lastly, Humminbird will send you an in hull to swap for the transom mount (it'll take several weeks to get one) but would be a no cost solution if Lowrance does the same. Something to check on their site or in the instructions.

Good luck

 

[extremez]

Re: drilling hole for transducer cable. need help

i did find this site earlier today but i couldn't find the parts that would fit and let my plug pass through. looking at the cable clam.

http://kfs.infopop.cc/groupee/forums/a/tpc/f/220603834/m/6821063181

i really dont want to drill and goop up the hole with sealant and have a mess. i think it will look tacky.

 

[JB]

Re: drilling hole for transducer cable. need help

Drill the hole. 1" sounds a bit big to me, but no matter.

Get a piece of hardwood dowel the same size as the hole and cut a slot in it that the cable alone will fit. Run the plug through and then thread the cable onto the dowel and slip it into the hole. Seal the ends of the dowel with 5200.

 

[rlk]

Re: drilling hole for transducer cable. need help

extremez, you do realize that the hole does not have to be below the water line don't you? Depending on your boat, you may be able to bring the transducer cable over the transom, and into the boat through the holes already in place for the steering cables, etc.

At a minimum, drill the hole as high as possible.

Bob

 

[Splat]

Re: drilling hole for transducer cable. need help

DO NOT CUT THE CABLE!!!!!!!!!!

You will not be able to properly shield the cable again if you caut it and you will get erronous readings!

Transducers are just like RF antennas, they are tuned to work properly for the frequency they operate at, cutting the cable and re soldering will cause signal loss.

Bill

 

[no1satguy]

Re: drilling hole for transducer cable. need help

Thank you for all the answers, I decided to drill a hole,I hope I am not hijacking your thread.

 

[NelsonQ]

Re: drilling hole for transducer cable. need help

no1satguy, no problem. That's why we're all here to learn something from these threads that we can apply to our own boats.

 

[extremez]

Re: drilling hole for transducer cable. need help

I haven't drilled the hole yet. as far as running it over the transom i could but it's a 18.5" fiberglass ski/fish with an I/O, so it has a back deck. i'm afraid if i do that it will pinch the cable and eventually break it.

i just wish there was some kind of fitting that i could use to make it look decent and not cobbed up.

 

[dingbat]

Re: drilling hole for transducer cable. need help

DO NOT CUT THE CABLE!!!!!!!!!!

You will not be able to properly shield the cable again if you caut it and you will get erronous readings!

Transducers are just like RF antennas, they are tuned to work properly for the frequency they operate at, cutting the cable and re soldering will cause signal loss.

A head unit calculates depth from pulses of the capacitance discharge of the transducer. Therefore the impedance of the cable would only come into play when lengthening the cable past 20 meters.

You will not encounter any problems at all should you decided to cut the transducer cable for routing. It's done all the time on installs. If you're not confident of your soldering skills they make "splice" boxes for just this situation.

I've used both of these cable ways with good success

http://www.westmarine.com/webapp/wc...L=true&storeNum=5003&subdeptNum=3&classNum=30

http://www.westmarine.com/webapp/wc...L=true&storeNum=6&subdeptNum=502&classNum=698

 

[rlk]

Re: drilling hole for transducer cable. need help

i just wish there was some kind of fitting that i could use to make it look decent and not cobbed up.

There is a fitting available to hide the hole, assuming you drill the hole above the water line. The fitting is mounted immediately above the hole. The bottom of the fitting is open for the cable to enter. The cable then turns 90 degrees to pass through the transom. A little caulk around the cable and the fitting and you are good to go.

Another thought is to mount the transducer inside the boat and shoot through the hull. No holes to drill.

Good luck, and let us know what you end up doing.

rlk

 

[Knot Waiting]

Re: drilling hole for transducer cable. need help

1" does sound a little big, but if that is what the instructions call for... Use a hole saw bit but.. run it in reverse first to score the gelcoat. Get it down past the finish this way. If you go full out in foward the bit will chew through the coat and bust it off in big flakes. Seal the hole very well with silicon and a cable plate if possible. If you can do it above the water line more power to you. Good luck

 

[extremez]

Re: drilling hole for transducer cable. need help

i drilled the hole today. calls for a 1" hole because the lowrance plug is huge. i bought a straight thru hull fitting and white silicone since the boat is white. i'm bringing the cable through above the water line. i'll post before and after pics.

 

[marcus.adelman]

Re: drilling hole for transducer cable. need help

Can't wait to see the pics because I have to do the same thing. I am not very eager to drill a 1" hole in my hull. Regardless where it is. I was thinking about taking the connector around and through the vent for my engine compartment but I am thinking that will look cheesy. My boat has a nice big swim deck to hide the sealed 1" hole though. The cable is so small. I wish they would have thought through the problem a little. I would be much more willing to drill a smaller hole. Considering the cable is like 1/8" thick.

 

[extremez]

Re: drilling hole for transducer cable. need help

ok, here's some pics. obviously you know the before shot would look like. so here's the finished product. i used a few sticky backed zip tie strips, a straight thru hull fitting and some 3m silicone.

The before

Halfway through, the tape is holding back the silicone i squeezed in from the other side.

Cable routing and mounting tabs

Close up of the thru hull fitting and silicone

 

[NelsonQ]

Re: drilling hole for transducer cable. need help

Great looking job.

By the way, anyone doing a Humminbird install may be interested in this other thread before they decide to relocate holes. I'm glad I did.

http://forums.iboats.com/showthread.php?t=225845&page=3