Depth finder transducer winterization

[MidnightRider]

Happened across the Owners Manual for the factory installed depth finder transducer (was stuck in bag with the boat Manual). There is a section in the manual for transducer called "Winterizing". This instructs you to remove the transducer to drain any water trapped between the through-hull-sleeve and the transducer itself to prevent possible breaking/cracking if the water were to freeze in there. It actually says remove "blanking plug" but that is because it earlier on says to remove the transducer and insert the blanking plug whenever you remove the boat from the water (so the blanking plug would in theory be installed at the time of winterization). Removing and installing blanking plug every time you pull it out of the water seems very excessive to me, but the fact that it says to remove it to drain water that may be in the sleeve concerns me. There isn't any difference in the sealing/o-ring configuration between the blanking plug and the actual transducer, so if water egress is possible with the plug, it is just as possible with the actual transducer. Anyone else see this manual? Anyone do this water draining procedure when winterizing? My concern about removing it would be to weaken the seal more than just leaving it alone. Plus I haven't looked to see how accessible this transducer is as far as doing this procedure. If I remember right I think it is in the bilge area which would require to unscrew and break the seal on the bilge cover to get at it. Who thinks this is worth doing? Or should it just be left it alone?

 

[MidnightRider]

Here is a capture of the manual.

 

[Jameson Clark]

Very interesting. This is definitely news to me. I look forward to hearing other's opinions on this.

 

[Dixie Highway]

That transducer looks to be very similar in design to an ultrasonic tank level transducer we use in industrial applications. If the bottom o-ring stays intact, there should be no water intrusion. That being said, I have removed these in a pressurized application and found water in between. There is also potential for condensation to form in between. Not enough to fill the sleeve, but a few good tablespoons worth.

 

[Whisky]

I've not done this, and when speaking with the technician they haven't mentioned doing it either.

Big picture, I suspect it isn't a problem..... until it is... haha

 

[Eric Ballard]

Seems like if you needed to do this you would need to do the same thing for the speed sensor too.

 

[MidnightRider]

Seems like if you needed to do this you would need to do the same thing for the speed sensor too.

You have a through hull speed sensor? Speed is GPS on this boat.

 

[RedBarron55]

I don't have one of these, but if you were to do something like fill the cavity on purpose with RV antifreeze it would preclude water entry and not freeze either.
Since the o'ring is at the bottom and top put the transducer almost all the way in, leaving room for addition of RV antifreeze, pour the cavity full and keep a little going while you put the transducer all the way in.
Use new O'rings and grease them with a little silicone grease.
For that matter fill the cavity with silicone grease if that sounds better.
I agree that it looks a lot like there is tittle difference in the form of the transducer and the blanking plug so I see little reason to not leave the transducer in place, taking some precautions

 

[MidnightRider]

I it was easier to get to I'd just pull them put some pool o-ring lube on them and put them back in. Just hate removing that bilge cover and all those screws that strip so easy and then having to reseal it all. I'm going to look and see if I can possibly reach it through the bilge access panel.

 

[haknslash]

I never use mine but I’m also not in a climate with extreme cold temps. You should be able to access the transducer if you remove the bilge access cover. On mine I have two access ports on each side of my clean out plug tube that I twist off. Not sure how the large boats are. Obviously unscrewing the entire tray would give you the most access. My arm barely fits in the access port and freaks me out lol.

 

[Ziess21]

Never done it on hundreds of boats and never had a problem...

 

[Bluewater272]

Left mine in last year, no problem. I have that plug around here somewhere, but I don't think I'm going to use it. Plan to touch that big possible hole as little as possible. You should be able to reach it through the bilge access cover if you're so inclined.

 

[RedBarron55]

If worried about the trapped water freezing fill the void with some silicone grease or oil.
Pull the transducer every ten years to check