What do you think of my thru hull condition?

[Capt. Caveman]

Hi All,

I'm a new member but have lurked here for a while gleaning information so thank you for that.

I have recently purchased a Jeanneau SO 42DS which I'm very happy with. Being new to boats I'm struggling to work out if my thru hulls are a concern. I have heard thru hulls are a general weakness of these boats so I would be very happy to hear what more experienced people think.

I did have the boat surveyed and pointed the surveyor towards them and he said their condition was fine. I asked how you can tell if there is imminent failure and he said they would start to weep first - does that sounds reasonable?

Thanks in advance.

[Phantom Jim]

This is not a proper below waterline through hull and the nipple appears to be rusting iron. The valve needs to be part of the through hull and bolted to the hull.

Best advice is to promptly replace this before the nipple fails and your boat sinks. Get a appropriately sized wooden plug and attach it to the hose so you have something to shove into the hole if, or when, the nipple fails.

[C420sailor]

100% absolutely replace.

If you have the room, install backing plates and proper seacocks. If not, do what you gotta do.

[Capt. Caveman]

It's that bad!? You can tell immediately that it is iron? I was planning to have the boat hauled out in approximately 6 months - if this was your boat would you wait or be calling boat yards to get it hauled out immediately?

This is my engine intake - is it equally alarming or not too bad? The others look a lot better.

[Allied39]

It may look worse than it is......but fine it is not.
I would hit it with a wire brush to remove the mess and see what the actual state of the fittings are and make a time line for replacement based on that.

The flange on the nut does appear to have corrosion that is more than surface.

I would NOT be happy if a thru hull of mine had such an appearance.

Thru hull fittings with ball valves atatched are perfectly fine. Of course properly installed with solid backing plates and properly maintained should go without saying.

[Cheechako]

Originally Posted by Capt. Caveman

It's that bad!? You can tell immediately that it is iron? I was planning to have the boat hauled out in approximately 6 months - if this was your boat would you wait or be calling boat yards to get it hauled out immediately?

This is my engine intake - is it equally alarming or not too bad? The others look a lot better.

Your first one appears to be SS. The rust on the mushroom fitting it attaches to bothers me.
The second one appears to be a bronze unit without the rust issue. It is typical of a lot of modern construction, albeit most of us would like to have a flanged seacock instead.

I would replace the rusty one pretty soon .... the problem with these things is there is no way to tell really. Could be fine for years or could break and sink the boat tomorrow.

The rusty threaded portion is typically very thin at the bottom of the thread groove. It's also a "stress riser" in the metal at it's thinnest part.. When new it might be 1/16" thick. Water pressure is minimal, but on an unflanged seacock (Flanges spreads the load via the wide base) , when you turn the handle or put any side force on it, that thin section at the thread root or valley takes some stress.....

[Capt. Caveman]

Just to confirm you're talking about the first thru hull I posted Allide?

Is there a danger of weakening the metal even further if I attack it with a wire brush? Don't get me wrong, I will be replacing it ASAP after the reactions here but I'm only with the boat for another 3 days (no time for haul out) and then need to leave it for a month. Is there anything I can do short term to strengthen it?

Massive thanks to everyone who has replied, this is exactly why I posted the question.

[Capt. Caveman]

Thanks Cheechako, this was exactly the guidance I was looking for. I'll email the previous owner and see if he has any more info on the material and when it was changed.

[s/v Jedi]

Study everything in the following link… every word of it!

The Groco flanged adapters will work great for you!

https://marinehowto.com/replacing-th...-and-seacocks/

[Cheechako]

Weakest link theory.... ....

[Allied39]

Originally Posted by Capt. Caveman

Just to confirm you're talking about the first thru hull I posted Allide?

Is there a danger of weakening the metal even further if I attack it with a wire brush? Don't get me wrong, I will be replacing it ASAP after the reactions here but I'm only with the boat for another 3 days (no time for haul out) and then need to leave it for a month. Is there anything I can do short term to strengthen it?

Massive thanks to everyone who has replied, this is exactly why I posted the question.

I was working off the first pic. I think you put the second pic up likely as I was posting.
I would not be in a panic calling boatyards. But this does need replacement.
To be dead honest I would likely make sure I had a plug about and I would put a fair whack of pressure on it, so I know if it's just sitting there or if it's pretty solid. But thats me.
If I broke it off I would simply deal with it, no big deal. But you likely do not have that level of ....um...familiarity with this type of thing.
So....where does that leave you? I think you might do well by not leaving that 6 months.
That could be replaced by someone who knows how to prepare for a job and get it done efficiently in less than an hour. A short haul.But you may not have access to that type of expertise....maybe?
And I would be willing to bet a beer that in all likelyhood after that is out and disected it shows to be pretty damn solid. But thats the issue.....you cant really tell until you have done that.

[C420sailor]

Went through my boat checking the thru-hulls. I suspect they were original. They didn’t look very corroded at all, but they were very discolored (dark) and just looked OLD.

I figured they were due for replacement from age alone, and went to remove the nuts. First one...nut disintegrated when I got the wrench on it. I was shocked. Broke into 8 pieces. I didn’t even use the wrench on the others. I used a hammer and a flat head screwdriver. A thwack shattered all but two of the nuts—those thru hulls I ground out.

Yours are both old and they look like hell. Time to replace.

Will you be okay until haul out? I’d say probably. Keep a good assortment of wood plugs and mallets handy (you should anyway) and avoid messing with the fittings/valves. Keep anything loose out of the compartments—you don’t want something rolling into it and snapping it off.

This fall though? Replace them all. Cheap insurance.

[Capt. Caveman]

Thanks for all the responses, the opinions are very welcome and I REALLY appreciate it. I'll look into getting them replaced asap.

[donradcliffe]

Their is a potential thru hull/seacock problem with all European boats after they changed their standards to allow boatbuilders to use brass instead of bronze. Your current seacock is a vulnerable to cracking off from kicks or trying to shut the valve and if it is indeed brass, it will self corrode in salt water. I would replace all brass with bronze at the next scheduled haulout, and handle gently until then.

[Tellie]

Surveyors, Ugh. When the obvious doesn't make his report I'd be concerned with what isn't so obvious that he is paid to find and has the same cavalier attitude towards.