While disconnecting and reconnecting a new macerator and ball valve to the thru hull, my eye thought it saw the thru hull turn, and shortly after I noticed it began to weep about one drop every 15-30 seconds. It stopped weeping after a few days. Someone on the dock told me it is because all the crud in the ocean probably plugged it up.
The thru hull I thought I saw turn is made out of plastic, and every boater I have talked to had a mostly bad opinion of plastic thru hulls. Some said, Marelon are ok, but most said plastic thru hulls are a disaster waiting to happen, and are to be avoided at all costs.
This prompted me to check my other thru hulls. The fist thru hulls I checked were in the head for the sink drain and seawater intake for toilet. As I studied them, I could not tell what they are made out of. So I dove on the boat to check them in the water.
When I got down there, I found something else a tad alarming: there are no external mushrooms on the water side covering either thru hull.
In fact, they haven't been there for so long that bottom paint is painted over where the mushrooms would normally cover, and that bottom paint was applied some three years ago. Who know how long it has been like that before the last bottom paint.
This alarms me because to my mind the thru hull mushrooms are there to provide backing strength to the thru hull.
So my question is this, is there any such thing as thru hulls that screw in that do not utilize an external mushoom to provide strength and a backing plate so the thru hull nut can be tighrened down?
When I stick my pinky into the thru hull from the water side, my finger goes in about a third of an inch before I come into contact with any internal thru hull material. Could the mushroom side of both thru hulls have broken off a long time ago, both escaping the attention of the bottom paint/boat yard, and my marine surveyor when I bought the boat?
Any advice/wisdom on this subject would be most appreciated.
All the best,
Joel S.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
Our 1989 has all marelon through hulls, with everything below the water line being "fair" to the hull. I believe they are called flush mount. Likely the same thing on your boat.
Dan & Amanda Reed
1989 Catalina 36 #947 Miss America
Fin Keel Std Rig
FL Panhandle
Joel - I also have an 89 and most of my through hulls are the flush mount type as well. Most are Marelon too but I'm not sure all are. The through hull on your macerator however - even if the leak stopped after a few days - would be a concern. It will likely require a haul-out to re-bed unless someone here has a magic trick up their sleeve.
_____________
Harold Baker
S/V Lucky Duck
Duncan Bay Boat Club
Cheboygan Michigan - Lake Huron
1989 C-36 mkI TR/WK M25XP
Ok, I looked up flush mounted thru hulls and attached a picture of what I found on the internet. In the picture, the flush mounted thru hull still has a side that is flanged on the water side of the hull to give it strength. I have nothing on the outside at all. From the water side, I have to put my pinky about 1/3 inch in the thru hull hole before I touch any thru hull material at all. Is it common for the flush side of the thru hull to break or fall off, or are there thru hulls that have no mushroom or flush flanging on the water side of the hull? I'm thinking I might be dealing with something dangerous here.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
Joel-
Make sure you have some tapered wooden bungs that could plug a hole if needed.
Is your flange nut on the inside of the hull loose?
If you can rotate the thru hull / valve back and forth- or rock it - check to make sure the flange nut is snug. Any leakage or movement that continues with a snug flange nut - well, if I were you, I'd pull the boat and examine closer what's going on. This time of year is typically slow for the lifts in the marinas and you should be able to negotiate a resonable price to haul out for a few hours and then drop back in.
My 2 cents
Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B
Sounds like you'll want a quick haul and hang at the least. Otherwise how could you trust it won't fail at worst possible time
les
Les & Trish Troyer
Mahalo
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor.
Commodore
Yes, I think you're right. Haul the sucker out. I don't hear anyone saying there are thru hull setups with no mushroom or flush flange on the outside. So I figure they broke off or disintegrated long ago and the only thing holding those things in are what remains in the thru hull hole. Not only that, the ball valve on one is getting stiff. Time to act. Thanks all.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
Joel,
I can't comment on the slow leak, but as far as the other thru-hulls, I think you are getting all worked up about nothing. Here's a link to the type of thru-hulls which have been installed on Catalinas for many years (Forespar). The pic you posted above is a skimpy plastic fitting to be used on a baitwell or similar. You do not need a mushroom fitting to provide strength. With a properly installed flush marelon (not plastic) fitting, including a backing plate, you should have no problems.
http://www.forespar.com/marelon-marine-boat-plumbing.shtml
Hope this helps.
Tom Sokoloski
C36/375IA Past Commodore
Noank, CT
The 93-series of Forespar valves primarily depend on the pull from the through-hull. If your king nut (valve flange) turned, then the sealant between the valve and the skin or backing block has failed. The Forespar flush-mount through-hull provides much more strength and contact area than the nylon scupper you show in your picture.
At some point, you're going to want to re-bed the entire assembly to bring it back to proper installation practices, i.e., a good bond between the king nut and the hull.
http://www.forespar.com/pdf/93SeriesValveInstallation.pdf
Nick Caballero
Retired C36/375IA Mk II Technical Editor
What I'm saying is whether it was a flush flange or a mushroom providing strength on the water side of the thru hull fitting, whatever was there, it is completely gone. There is nothing, not even a remnant on the water side of the thru hull. All that is left is the part that screws inside the hole in the hull, and I have to put my finger about a third of an inch inside the water side of that hole before my figure touches what remains of whatever was originally installed. So unless there are thru hull fittings that are made with no flush or mushroom flange on the water side, it would appear mine broke off or disintegrated. That is what had got me worried. Now if you are saying there is nothing to worry about if that part of the thru hull fitting is no longer there, or that my thru hull fitting was likely made that way, I'm all ears.
Does anyone else have a thru hull fitting that has no flush or mushroom flange on the water side of the hull? Is it possible it came stock set up that way? If the mushroom or flush flange breaks off or disintegrates, is what remains of the thru hull fitting generally still reliable? These are the things I want to know.
All the best--Joel S.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
Jas
Pretty much everyone here is saying pull the boat and see what's going on. I agree.
Reminds me of a story about the guy who got shot by an arrow but wouldn't let the doctor touch him until he knew the name of the person who shot it, where he lived, what nationality or clan he was from, what material the feathers were made from ect. ect.
David
2003 Catalina 36
Not knowing anything about thru hulls, except what they do, I was hoping that I would find somebody who understoid what I was looking at, and point me to a process by which I could arrive at a more definitive understanding. What I'm seeing is mixed opinions. If that holds, I will pull the boat. However, I'm still holding out a small hope that someone who understands what I am seeing will come out of the woodwork and say "lots of boats have thru hulls with no mushrooms or flush flanges and they are just fine...if they are sealed properly on the inside, that's what counts" or some such similar comment. Unfortunately, it doesn't look like such a comment will be forthcoming...which probably means I will be spending a bunch more money after just spending a bunch more money. But as they say on the docks..."what'd you expect, you bought a boat."
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
And no, I'm am like a guy who is alarmed by a couple of thru hull fittings and wondering if it's a serious issue or more or less normal. A completely rational question given the costs associated with pulling a boat and replacing the thru hulls.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
Duplicate.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
Joel-
If the outside mushroom head or flush mount flange broke off, wouldn't you have seen an area with no bottom paint when you dove or when the boat was on the hard before launch?
I think some thru hull flanges are seated in a countersunk depression on the hull exterior. With bottom paint build up, this could give the appearance that the flange is non existant. This might be what you were seeing when you dove to take a look.
Bottom line- if there is any water seeping in, or you can create motion by rotation or rocking the fitting from the inside of the hull, the boat should be hauled
Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B
Let's see. (1) no flange or mushroom on the through-hull, (2) just a broken stem inside the hole, and (3) the seacock flange turns. If all true, then you should at least get a short-haul ASAP and investigate.
When you're hauled, since the seacock turns, you might be able to leave the through-hull as-is and unscrew the seacock from the inside of the boat. Once you do this, there should be the threaded portion of the through-hull exposed and you should able to coerce this out. At that point, install a new through-hull (Marelon) following the instructions I pointed to in my earlier post. This is not for the timid, so there's no shame in contracting the yard to do the work.
Please take pictures of what you find. Best of luck.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
Thanks Nick. The thru hull that I *thought* I saw turn was a third thru hull that connects to the macerator. And it did leak (very slowly) for a little whIle and then stopped. As I contemplated replacing that thru hull, I decided to check the others, at which time I ran into the two missing mushrooms/or flush flanges that belong to the thru hulls in the head. If I do wind up haulin it out, I will likely replace all the thru hulls just to be safe.
Btw, an old salt at my previous marina told me that I should always carry a wax toilet gasket on board just in case I ever need to plug a hole in a hurry. He said he once replaced a thru hull in the water using wax toilet gasket material on the water side to keep the ocean out while he completed the job.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
Thanks for your reply, Paul. There are what look like little round depressions in the hull around the thru hull openings. These depressions are covered with the same bottom paint as the rest of the hull below the water line. It didn't look like they were painted over flush flanges, but rather round depressions where the flush flanges would seat. It's possible the flush flanges have been covered up by the paint, but I doubt it, there were no seems at all as far as I could detect. I will dive on the boat again and see if I can see any sign of what you are talking about.
As for the yard missing them, that has got me perplexed as well, and makes me think that what I'm looking at may be "normal". Nobody mentioned it when the boat was hauled out and surveyed, and nobody mentioned it when my boat was hauled out and bottom painted either. As for me, other than blisters and bottom paint, I had no idea what else I should be looking for when they hauled it out for the survey.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California