Replace depth sensor without taking out of the water?

[stnick]

Most 99 percent transducers are made by airmar . There are two frequencies in total .
If you get a thru hull you can use it inside and it will shoot thru the fiberglass hull . I have done this with perfect results. in stead of filling the clear plastic bubble around it use silicone caulk . Sticks and works perfect . No mess no leaks !

[Russ]

Two points

Having replaced my sounder on the hard. Be prepared to breakthrough a lot of 3M 5200 from the original application to get the current one out. B

Two: We used to have a saying “ Just because you CAN do something , Doesn’t mean it’s the Right thing to do”
I understand saving money but this is all pretty half baked in order to save money at a critical point of failure—— Like a 2 1/2” hole in the hull below the waterline!

Russ

[doublewide]

A small hole can be plugged effectively as a temporizing measure by a Nerf-ball. We carry various sizes with us just in case. The American-football-shaped Nerf balls may be the best. And they are inexpensive, dual use devices. You can play catch with them, too.

[David M]

Sorry, but I think that risking sinking you boat over trying to save $800 bucks or whatever is the ultimate in being cheap. No offense intended.

Ask what would happen if your insurance company got wind of this after trying to file a claim.

[billgewater]

I would be asking myself why one would be replacing a transducer. If it is an old 200 khz transducer, you can buy an independent instrument e.g. an advanSea depth S400 which is designed to specifically work on these older single frequency 200 khz transducers. Contact www.advansea.com. Not cheap, but I have used one to replace a NZ Navman Depth 3100 instrument that suffered from screen failure. (The NZ company no longer exists. Even the mounting hole for the advanSea instrument matches the Navman instrument). Works perfectly.
If the transducer has failed (never heard of that happening before!) then .......
The Raymarine i40 models etc. which are dual frequency (50 and 200 khz) just simply don't work well on the single frequency older transducers. (If anyone has had success please let me know how they did it!)
If you try to replace the existing transducer in the water, I would advise that you check your auto bilge pumps and also the ready access to lift out facilities. best of ....

[elandra65]

I am sure you could just hold a plunger over the hole until a diver could get their hand over the hole and then insert the wire end through their fingers without letting too much water in.
If you use butyl mastic tape placed around the thru hull there will be no problem with sealant.

However you may find the old transducer stuck in with 5200 or similar evil muck. I had to totally destroy my old fitting with a sledge hammer to get it out for that reason. No easy way to do that in the water. The other option and what I did was get the boat lifted and replace in the slings. Sometimes marinas do a lift and pressure wash special which is what I did. They let me replace the transducer while in the slings. If you use butyl mastic tape there is no waiting time to go off and you can go back in the water straight away.

It is amazing what can be done in the water to save money. I have replaced valves, props and even a prop shaft in the water. Be very organised and have a plan b in case it goes pear shaped. It can be quite stressful too.

Good luck

Andrew

[steveh2112]

i never expected so many great replies to this post, i thought it was a stupid question but lots of good advice here

i'm going to the boat now to try the sensor inside the hull. if that works, it will do until the next haul out.

i just remembered the replacement depth transducer i bought is the removable sleeve type, so all i have to install under the boat is the plastic sleeve. once that is in secure, i just pop in the transducer from above, just like the speed one.

so probably a simple diver replacement job so long as i can contain the water

[smac999]

normally removing a transducer takes hours of swearing, banging, and normally ending up breaking it out in pieces. and that's out of water working from both sides. "pushing it out" into a bucket from above is laughable. also sealing it from the inside only is not good. (I guess that's why you were able to push it out?...) the face of it needs to be sealed on the outside, before it is pushed into the hull.

consider getting an inhull to tie you over untill the next planned haul out?

a thrull hull trasducer mounted inside is not great. they need to be water cooled and will overhead and damage themselves not in water.

[steveh2112]

So Paul, i owe you a beer, you saved me $800.

I put a blob of vaseline in the center of the transducer and a ring of sikaflex around the outer edge and stuck it down just in front of the original transducer, and it works perfect!!!!!

there is about a 20cm error in depth as far as i can tell by measuring the depth with a tape measure, but no biggee as i can compensate for that in the tridata

so all good, and i'll do the permanent install next time the boat come out.

glad i asked my insane question

[.Paul.]

Steve,

Good to hear that you got it to work!

Paul