Adding a new thru-hull

[nor'easter]

I have a dock neighbor that wants to add a bait system and may need to add a thru hull. He was advised by a marine service guy that it can be done in the water using a diver and a plunger after drilling a pilot hole, etc. sounds hokey to me, but I don't know if it reasonable or not. His tech is confident in this technique and has done it many times. He has no plans for a haul and has decent bottom paint, so no need for a haul except for this.

What do you think? Is this a reasonable thing to do?

 

[Glory]

That can be done, making a dry water seal is anothr thing.

A haul and and thru bolted sea cock is the correct way to go.

JM

 

[Boatsb]

Is there a fresh water wash down? I would tee off it and not make another hole.

 

[nor'easter]

I said the same thing about a T but he said that he isn't sure about a salt water intake for a wash down. He thinks the only wash down he has is fresh. It is a carver or silver ton cockpit motor yacht I think. I can't imagine doing this in the water on my own boat. The owner sees the savings from the haul out as a big bonus I guess.

Thanks for the input.

 

[jim rosenthal]

Yeah, and think of the exercise he'll get running around like crazy when something goes wrong and he has to move the boat to the lift well as it's trying to sink. You should sell tickets to this circus.

You can't get a good install when this is done in a hurry. The cost of a haulout, not only to do the install but to let things dry so that your sealant actually seals and does what it's supposed to- that cost is part of the whole affair. If he doesn't want to spend it, he ought to forego the new through hull and just save all his money. Trying to do this in the water- a new installation- is false economy and that's being kind. IMHO, it's a damn bad idea.

 

[Boatsb]

A haul out is a couple of hundred dollars to do it as a short haul and hang in the slings over lunch. The diver will cost almost that much and then there is the %*#K factor that Murphy brings. If he needs it do the haul. If its not that necessary wait for the next haul. In water repairs are one thing but to make a hole on purpose is just crazy.

 

[SeaWhisper]

I said the same thing about a T but he said that he isn't sure about a salt water intake for a wash down. He thinks the only wash down he has is fresh. It is a carver or silver ton cockpit motor yacht I think. I can't imagine doing this in the water on my own boat. The owner sees the savings from the haul out as a big bonus I guess.

Thanks for the input.

You mention that the yacht is a Carver or Silverton model... Does the hull have a balsa core? I would pull the boat out of the water. Drill the hole seal off the balsa core with epoxy. Then do a proper bedding of the thru hull fitting.

 

[MikeP]

I know people do it and yeah, 5200 will cure underwater. But this is one of those things where if a friend at the marina said, "Will you help me install a thru-hull in my boat while it's in the water," I'd probably say, "Sure, if you know how to do it." What the heck, who doesn't like a circus? But I'd never do it on my boat - changing the packing in stuffing box makes me pretty nervous even though I've done it several times.

I agree that the haul out is the only smart way. This isn't an emergency - why take a chance on making it one?

 

[nor'easter]

Thanks all. Seems like a nice guy. I will pass this along. I don't know about the bottom being cored. He doesn't seem like big time fisherman, and it is not a fishing boat, so I think he will take the advice from someone with nothing to gain and wait.

 

[rsmith]

Its not that big a deal. There is not that much pressure of water coming in the boat. In the bad old days transducers went bad all the time.I changed them in the water all the time. I even still carry 2 spares for mine. A rag will easily stop the water flow. The hardest thing is driving the old transducer off which usualy takes a couple wacks with a dead blow hammer. Then I take a fishing line or parachute cord with a weight and drop it thru the hole til it hits the bottom. Remember to put it the nut washer and fairing block first. Stuff a rag in the hole. Then reach under the boat with a long boat hook or gaff. Usually a couple swipes will snag the line. pull it up on the boat and tie the transducer wire to the fish line. If Im doing a thru hull I use a small stick or piece of ply wood to bridge the hole across the opening. Goober it up with 5200 throw it overboard then pull it up thru the hull. Then the trick is to tighten the nut with out damaging the threads. I use a rag or piece of rubber with a pair of chanelocks, you dont need to kill it. Most people overtighten everything. If its somthing that needs orientation I put a mark on the stem. Ive done it this way many times by myself without ever getting my feet wet.
Most people may get panicy about a little water coming in the boat but think about this If you fill your water tank from a hose thats flowing a lot harder than thru hull how long does it take 30 min 40 min?? and it doesent come even near to sinking the boat. The way I do it maybe you'll get free flow for a minute?

 

[jim rosenthal]

Yeah, but they are talking about making a new hole in the boat. If they decide to do this in the water, they ought to sell tickets to this one. Or shoot a video and upload it to YT. Like Scott said, they could just do a haul and hang in the slings and have it all done in an hour or so- I did that a few years ago when I needed to change a trim tab cylinder that was leaking hydraulic oil into the water. The peace of mind was well worth it, and I got a chance to check everything else out at the same time. Like Mike says, why make it an emergency?

 

[SKYCHENEY]

It's not a Hatteras, so go for it. If it sinks, that will be one less ugly boat we have to look at.

 

[rsmith]

it's not a hatteras, so go for it. If it sinks, that will be one less ugly boat we have to look at.

bhahaha agreed!!!

 

[dsharp]

Kinda what I was thinking when he said it was a carver.