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Temporary Plug for Thru Hull Fitting

Jan 10, 2016
126
Islander Wayfarer 37 Sloop Key West
So, a friend bought a sailboat............without asking my opinion of it first. Let's be kind and say the boat needs, uh, work.
Since this is a live-aboard, the first order of business is a working head. Installed now is your standard issue Jabesco and I will replace it with the same as well as replacing the waste impregnated hoses and stainless clamps. The boat is in the water.

Now my question, since I believe in Murphy's Law and live by my Dad's motto, "Hope for the best, expect the worst" I want to temporarily plug the through-hull fitting for waste, (which of course is below the waterline) to protect the boat from flooding in the event I break the seacock or suffer some other misadventure.

My thought is to use a plug like is used to plug plumbing pipes to test for leaks.plug.jpg

You have no idea how much I would appreciate guidance on this operation.
 
Sep 25, 2008
5,860
Alden 50 Sarasota, Florida
temporary fittings are probably not wise particularly where failure can be catastrophic. Doesn’t the thruhull have a seacock (shutoff)? If not, how do you plan to remove the impregnated hose?
 
Oct 22, 2014
13,136
CAL 35 Cruiser moored EVERETT WA
:plus: the traditional emergency fix @justsomeguy

there are a few variations like.
  • Stay Afloat Emergency Leak Sealant
  • then there is the rubber plug.

    FORESPAR–Sta-Plug® Emergency Plug

 
Jan 10, 2016
126
Islander Wayfarer 37 Sloop Key West
Thanks Justsomeguy, those plugs look great.

Not sure I made myself clear.

Yes, there is a seacock and yes I will shut it before removing the hose. My concern is when shutting the old, crusty looking seacock and disturbing this fitting I want a second layer of protection in case I damage the seacock or even snap it off the thru-hull fitting. I want something to use just as I would use if I needed to replace the seacock.

It seems so simple to me. I insert the plug, close the seacock, remove the hose and if nothing breaks replace the hose, remove the plug and open the seacock.

Those emergency plugs look like they are meant to be hammered home for 1 use. Last thing I want to do is stress this area.
 
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Jan 10, 2016
126
Islander Wayfarer 37 Sloop Key West
Just read the instructions on this -> FORESPAR–Sta-Plug® Emergency Plug

It says just twist and insert by hand, I like that
 
Oct 22, 2014
13,136
CAL 35 Cruiser moored EVERETT WA
Jim. Safe is a short haul to assure that the seacock has not failed. If failed you may be replacing both seacock and thru hull.

This seacock looked ok. I was worried about its sister next to it. When I attempted to work it the seacock came apart in my hand. It had deteriorated on the inside. Sometimes you never know. I am thankful it happens while I was out of the water.

How the Valve looked before I hauled the boat.
old but serviceable. Never an issue opening or closing the valve.
82AFDAE7-53FE-401A-829E-A3EAC5DE9446.jpeg0FF02F58-1B83-4632-9464-4F50A0A7FE34.jpeg

what happened when I tried to remove the valve so I could inspect/replace the thru hull
B692C79A-32FF-4A5A-9335-DCDBBDE8F979.jpeg9DC27ADF-20D6-407D-8F06-1A017A354344.jpeg

Turned out to be a just in time fix.
 
May 24, 2004
6,519
CC 30 South Florida
I was prepping a boat for a Hurricane and went to close the gate valve to the galley sink discharge and it just disintegrated in may hand. Grabbed a rag and stuffed it down the thru-hull and held it in place with duct tape. It slowed the water intrusion down to a small trickle to give me a chance to figure out what to do. In the chaos of a coming storm there was no haul out to be considered nor a chance to install a new thru-hull and valve. Removed the tape and cleaned out the threads to the thru-hull, measured the size and the type of threads and went to a hardware store for a piece of pipe, a couple of fittings and a screw on plug. Back at the boat threaded a fitting, threaded the pipe, another fitting and the screwed the plug in. It worked to stop the inflow. The boat and the rigged plug survived the storm. Thanks to a rag and duct tape.
 
Nov 18, 2010
2,424
Catalina 310 Hingham, MA
Jim. Safe is a short haul to assure that the seacock has not failed. If failed you may be replacing both seacock and thru hull.

This seacock looked ok. I was worried about its sister next to it. When I attempted to work it the seacock came apart in my hand. It had deteriorated on the inside. Sometimes you never know. I am thankful it happens while I was out of the water.

How the Valve looked before I hauled the boat.
old but serviceable. Never an issue opening or closing the valve.
View attachment 185644View attachment 185645

what happened when I tried to remove the valve so I could inspect/replace the thru hull
View attachment 185640View attachment 185641

Turned out to be a just in time fix.
These should have been a red flag from the beginning. These are NOT seacocks. This is a ball valve threaded onto a through hull. More over they look to be brass instead of bronze.

I recommend all start with reading this article from Mainesail. Seacock & Thru-Hull Primer - Marine How To

Fair winds and good luck,

Jesse
 
Jan 10, 2016
126
Islander Wayfarer 37 Sloop Key West
Sounds like I'm not being over cautious, those stories are just the thing I want to avoid. In my research I read that the fittings should always be bronze and never mix brass with bronze or the brass will disintegrate as the sacrificial metal. The plugs I first mentioned are used in plumbing to pressure test pipes and come in different sizes and work same as the drain plugs in a boat transom. If I can get the right size I would like to try that with the emergency plug on hand for backup. If I can just shut the seacock (I haven't even touched it yet) I will wait till the next haulout to inspect the fittings and replace those hoses. I think the waste seacock is Marelon screwed onto a bronze thru hull fitting.
 
Jan 10, 2016
126
Islander Wayfarer 37 Sloop Key West
Thanks for that article Jesse, I didn't see it until after I sent my last reply.
 
Jan 10, 2016
126
Islander Wayfarer 37 Sloop Key West
Here's a pic of the head with the loop behind it. Since the loop is above the waterline, is it OK to change the hose from head to loop? Still itching to shut that waste seacock but I'll be satisfied for now just to change out the head. The head needs rebuilt and the kits cost nearly as much us a new head so I'm starting fresh and replacing the whole unit. Guess I'll do the hoses and seacocks when hauled out.
loop.jpg
 
Oct 22, 2014
13,136
CAL 35 Cruiser moored EVERETT WA
Oh Jim... That looks to be a messy task. Flush Clean the tanks and suck all the hoses using a disposal system first. You can deal with a dirty hose if the hoses contents have been flushed clean and the tanks emptied. If you have blockage in the hoses there is not a mask the can protect your nose from the stench. Then is when I resort to a dab of Vicks under my nose and short exposure time events.
 
Jan 10, 2016
126
Islander Wayfarer 37 Sloop Key West
The head is not being used except to pump fresh water and vinegar through and the holding tank gets a pump out weekly. but with the joker valve not working right it's hard to get a good flush. I will use your suggestion using Vicks. Funny, the head kept backfilling, most likely from the joker valve, so to empty it I used a shop vac. Thirty seconds later I was scrambling up the companionway with the dry heaves. You can imagine the fumes coming out the exhaust side of the vac.
 
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Likes: jssailem
Nov 16, 2012
930
Catalina 310, 2000, #31 Santa Cruz
Jim, check out the Raritan replacement that (I think) let’s you keep the bowl, but gives you a much better built pump unit. Or just replace the entire thing with a Raritan unit. We did that and have been very happy with the Raritan. Pretty sure Peggy would r3commend doing that.
 
May 17, 2004
2,781
Beneteau Oceanis 37 LE Havre de Grace
Here's a pic of the head with the loop behind it. Since the loop is above the waterline, is it OK to change the hose from head to loop? Still itching to shut that waste seacock but I'll be satisfied for now just to change out the head. The head needs rebuilt and the kits cost nearly as much us a new head so I'm starting fresh and replacing the whole unit. Guess I'll do the hoses and seacocks when hauled out.View attachment 185692
As long as you’re sure the top of the loop is at least a few inches above the waterline then I agree you should be safe to replace that section of hose. But with regard to leaving the seacock open, you need to weigh those risks carefully. You’re basically trading one risk (that the seacock could fail when being closed) with another (that some other hose or fitting inside the seacock could fail with the seacock open). Moving the hoses and fittings around to do things like update the plumbing only increase the chances that the outermost section of existing hose could crack and fail. If it were me I’d probably hold the body of the seacock firm and gingerly try moving the handle to see if it could be moved without moving the body too much.
 
Jan 10, 2016
126
Islander Wayfarer 37 Sloop Key West
So, finally getting my head around the head and it's tributaries I realized so long as the holding tank is above the waterline I can replace all the hoses from head to tank with no worries of flooding the boat. The last hose to remove went into the top of the holding tank and wouldn't you know it, the fitting broke. (see photo)

shit.jpg

The top, small hose is the vent, the hose below to the right goes to a Y valve pumpout/macerator) and the hole to the left is where the hose coming from the head should attach. The tank looks very old and I'm wondering how to proceed. Let me say right here that this is a low budget project until we have all systems working and decide whether the boat is worth putting any real money into. My first thought is to attempt to epoxy the neck of the broken fitting and gently reattach the new hose but I don't know what kind of plastic this is and what will hold. Second thought is to replace the round tank cover but I have no idea if it is possible to find something that looks like the pic. Third is to make my own tank top cover with 3 new fittings. Lastly (because we would like to one day put in a larger tank but not now). is to replace the tank with another the same as what's in now.

So, asking for help again. Sorry to stink up the forum but believe me, it's worse on my end.

In with the boats paperwork was a manual for the Jabesco Y valve with this pic. The tank looks just like this. Maybe an old Jabesco tank?
jabesco.jpg
 
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