need helpful hints for replacing fishfinder

[Lloyd345]

Hi,

Between rough handling by marina forklift operators (damaging the transducer) and my own error in leaving the fishfinder in the sun too long (damage to screen), I'm due for a new fishfinder. I picked up a Raymarine L470 fishfinder. Before I embark on the replacement, I thought I'd post this thread to ask for helpful hints from those of you who have experience with this sort of thing. I'll mention a few areas of concern to prompt your thoughts:

The base for the LCD display for the previous fishfinder is not going to come off the center console dashboard easily. I already unscrewed the base, but it appears some kind of strong sealant was used. I tried using a razorblade around the edges of the base and a screwdriver to pry it off, to no avail. Suggestions?

The old transom mounted transducer and the cable need to come out. What's the best way to seal the old holes (where transom is attached)?

The 19'7" Neptune Sunbird doesn't leave a lot of room for running cables or getting a hold of things. I anticipate challenges with running the new cable from the console to the transom as it needs to meander through inaccessible, tight spaces. I'd imagine I want to attach the new cable to the old one and pull it through, but electrical tape probably won't suffice to keep the two cables together. Thoughts?

Regarding EMC guidelines, the insruction book says to allow plenty of space between wires for different electrical units. The transducer cable can't help but run near the VHF radio wire and the starter wire, so what do you suggest?

The new power cable includes a smaller shield wire for connection to a good ground. What would that "good ground" be? I think the approach with the new power cable is to some how connect it to the wire running to the console "accessories" fuse (rather than running it back to the battery).

Thanks for any tips...

 

[tashasdaddy]

Re: need helpful hints for replacing fishfinder

mines power buy the fuse block, and grounded to the common ground, under the console. if you can use the old hole in the transom, if not fill with epoxy, to seal where the wires run thru 4200 is good and on the new screw holes. when mounting the screen i cut a rubber gasket, and screw mine stuff on, rather than using a sticky substance, incase of replacement. to get the present base of, i'd try taking a razor or exacto knife, and work the edges, hopefully buy working all the way around the console won't chip, and if it does maybe the new one will cover it. i bought some 54' vinyl and made a cover for my center console,

 

[WTPhantom309]

Re: need helpful hints for replacing fishfinder

Lloyd, youd be suprised what electrical tape will hold(I know im an electrician). What i did on my dads bass cat was before i pulled the(old) transducer wire out I taped a peice of 14 gauge wire to it and pulled it back, then i attached the (new) trans wire to the 14 gauge and taped it up good. You might find some one to give you a hand, when pulling the wire through and you feel like its in a bind have them pull back and keep working with it youll get it. The best tape ive found is what we call "88", 3M's "88" hold really good just wrap it flat and tight. as for hooking it up if ur not comfortable with the ground under the dash pull and extra 14 or so gauge wire through and hook to the - side of the batt. good luck!!


Derek

P.S. Ive pulled many of wires with "88" over the last few years , and , ive learned that if you take ur time and dont pull too hard it come on through like gas through a funnel.

 

[Lloyd345]

Re: need helpful hints for replacing fishfinder

Well, I took off the old transducers and put on the new one. What a messy job...the instructions said to put sealant on the screw shaft...of course, the white sealant is all over the transducer and still on my hands (days later).

Now I have several open screw holes below water line where the old transducers used to be. So what's the right way to seal these screw holes? I've considered grabbing the old screws and putting sealant on the screw shaft and just screwing them back in the holes; I've also considered just squeezing sealant into the hole with hopes it'll keep water out. Suggestions???

 

[jtexas]

Re: need helpful hints for replacing fishfinder

screws loaded up with 5200 would do it...but to me, this sounds like a job for Marine-tex