How to replace transducer without sinking

[topmast]

Installing a new hole in the hull or just replacing the bronze bit is no biggie for two fart smellers.One in the water with a toilet plunger ,other in side with drill. and a hose to fit new hole and reach above the wl. Pilot hole to locate plunger,drill full size and stick in hose. New fitting with a bung rams in from outside to displace hose. valve installed and bung pulled out (its long enough to get a grip on.) If its a transducer. drop a nut on a string down the hose. Diver brings it up to surface to tie on wire (aligning block and goop included and feeds wire back up the hole Hose is displaced and inside aligning block and nut is feed down the wire by inside guy. Cheaper than haul out for a big boat.

[Pete7]

Originally Posted by Chuck Hawley

1. If you're thinking of replacing the entire through hull, that's a job for a haulout. It would take extenuating circumstances for me to try to do this with the boat in the water (like no boatyard within 1000 miles).

Perhaps, but I have used a bucket before to replace a transducer. Use 15mm expanded foam pipe insulation to line the rim of the bucket. Place new transducer in bucket and pass to divers. Divers take bucket down and place over existing transducer. and hold in place on the outside of the hull. Tap on the hull means knock out the old transducer into the bucket. As soon as this happens water pressure hold bucket onto hull. Use coat hanger to fish new transducer wire into hole and pull through. Fit transducer and tell divers to remove bucket without dropping the old transducer.

Pete

[Moreorless]

I have used the following method to change the transducer and one broken through hull fitting. Have another person help you to steer and be lookout, take the boat out to full cruising speed, then go below and take out the transducer. Less then a cup of water will come in and you will have ample time to put in a plug. Then stop the boat and do your maintenance.

Water at the speed it will be doing under your boat cannot make a ninety degree turn. You will get very little water in the boat.

[Pete7]

Hmm, would like to try that, on someone else's boat you understand

[jheldatksuedu]

The bucket Idea works great, and gives you plenty of time, put the new transducer or whatever will not fit through the hole in the bucket before you press it against the hull. An air bag or rope can hold it against the hull while you install it, but a much easier method is to provide a slow leak from a slightly removed transducer, it will grab it and hold it almost immediately after you install it. Also the water pressure can collapse the bucket so it would be good to reinforce it. It amazed me that 18 inches of depth could have this much force. The pictures don't show it but the final version had a wood cross about 1/2 way down inside the 5 gal bucket to keep it from collapsing. You can suck all the water out of the bucket using a vacuum cleaner through the hole. You can see what I tried and what worked and didn't work on my website. I do this all single handed. Click on the repair at sea link below.

Repair at Sea

[OS2Dude]

Make VERY VERY sure the size is the same. Most of the more modern transducers I've seen are completely different in size from the older ones. If all you need is depth, consider an In-Hull transducer, at least until your next haul out. That is what we did with our boat. Simply disconnected the wires for the existing one and install the in-hull nearby. No Problem. Next haul out I will patch the existing thru-hull...

[captstu]

If you were replacing a transducer within an existing ring there is no problem pull it out put the new one clean the mess up.

If the unit is a single piece that must come out of the hall as one unit,you can dive below with the coffee can tap the old unit into the coffee tea and that is holding the new unit fish the wire up through the hole with a coathanger pulled into place. I did this on my boat and the cleanup involved one whole rag worth of water.

[rpjn59]

Hi, yeah it's a little disconcerting, but's no big deal. 1-check if your bilge pump is working properly, really good piece of mind. 2- have the process worked out in your head. 3- don't panic work quickishly. 4- do not cross thread the fitting, work it counterclockwise until you feel the threads mate and then go clockwise. 5-you'll have a good laugh when it's over and another notch in seamanship skills(think twice before getting that 'tall ship' tattooed on your chest, argh.

[TomLewis]

Used to clean little shrimp from the paddlewheel regularly. We would just stick a bung in temporarily, clean the wheel, then remove the bung and replace the transducer. Very little water came in.

[sainted]

Oh dear, oh dear, oh dear. All of the advise previously given is good.

I've installed new thru hulls whilst a vessel was afloat. Two people were required, an inside and an outside man (or woman). The inside guy had a hole saw of the appropriate diameter. The outside guy (a diver) had a plunger and the new thru hull gooped with 5200 (yes, it works underwater). The inside guy drills a hole thru the hull with the hole saw and the diver covers it with the plunger as he does so (he sees the pilot hole!!). Quick as lightening, the diver pulls the plunger off and pushes the new thru hull home. The inside guy puts on the nut, and that's that.

However, in this case, the OP was less than clear about what needed to be done. Many of the previous posts postulated that merely changing the sender in an existing thru hull was possible. Other postulated that removing the existing thru hull and replacing it with another of the same diameter was what was required.

We don't know. The OP didn't say.

And here's the thing. I work in a boat yard and have removed a fair number of thru hulls. The problem is, a lot of those thru hulls were glued in with 5200, which is a damned good adhesive. Our SOP (standard operating procedure) is to cut the heads off thru hulls and beat them out of the hull with a hammer. I know, it sounds excessive, but that's by far the fastest way to get a thru hull out that's been glued in with 5200. And most of them have. This is not a procedure that can be done afloat.

If the OP wants to install a new thru hull, sender or what have you in a new hole, it can be done afloat.

If he wants to take out an existing, well bedded thru hull and replace it with a new one (presuming they are the same diameter), I strongly recommend pulling the boat. If you work with the yard (i.e., explain what you want to do), they'll likely leave the boat in the slings whilst they swap the thru hull for you and give you a discount on the haul out.

That's my 2 cents.

[TrentePieds]

Quote: " The problem is, a lot of those thru hulls were glued in with 5200, which is a damned good adhesive."

Agreed. And the OP can't know if the thru-hull has been screwed, blued and five-two-ed. Doing an exchange of thru-hulls afloat is dodgy unless that is known.

I have a much easier but still annoying problem: The PO spent a shameful amount of money on a new rig, including four new Anderson winches. They are gooped down with 5200. The stripper bars are all wrongly oriented, one so badly that the winch is effectively no longer a self-tailer. On Andersons you cannot re-orient the stripper bar in relation to the winch body. You have to shift the winch body in relation to the gorilla's work position.

This job calls for a small hydraulic jack, some wedges and some fairly blue language :-)!

TrentePieds

[ingrid75]

Then be a prudent seaman and haul the boat NOW. If you get cute and try some kind of voodoo to change the transducer, and anything goes wrong......well, you bet your boat.

[tuffr2]

Can't the bilge pump kinda keep up with the water coming it. Maybe not 100% of it but 75% - 80 %?

Sent from my SM-G360V using Cruisers Sailing Forum mobile app

[Stu Jackson]

With the knotmeter, however, the display was fine but all it read was "0.0." The first step was to replace the paddlewheel. The old one looked just fine, clear of any growth, but I replaced it anyway. Of course, this was done in the water. I have gotten quite good at this and my trick is this: Being right handed my first thought was to remove the transducer with my right hand and install the plug with my left, but I found out that doing it just the other way worked much better, since I could insert the plug more quickly and cleanly with my right hand, greatly reducing the intrusion of water from that big hole. Our transducer is below the wall in the V berth. We have a lower drawer there, which came from the galley because our PO had installed a microwave oven below the galley sink. Great access makes a big difference. Replacing the paddlewheel didn't work.

[knockabout]

a 2"hole sounds like a compete replacement not pull the pin out and pull the sender and paddle wheel out /have a new old interphase not fitted yet the transducer came with a blank plug/ has some lube on the oring


the tide range here is over 6 mtrs and we have a mud pen to dry the boat out between tides


your other question a product called seal once will set under water and adhere to an oily surface /