Replacing all Thru Hauls

[Amaranth]

I am about to replace all the bronze thru hulls in a racing yacht of which there are 14.

Thinking about drag, I was wondering if anybody had heard of or know about low profile type thru hulls ??

[rbk]

If you’re looking at replacing with bronze then yes Groco 100% for sure makes a flush mount thru hull. They also come in stainless steel as well (fairly certain) but you’ll have an easier time finding all the bronze fittings you’ll need.

Edit* did not mean to add angry face to top. No idea how to remove sorry.

[Dsanduril]

I prefer plastic to metal as I've seen metal failures but lots of room for debate there.

TruDesign make a very nice line of flush mount plastic skin fittings.

If you want metal Buck Algonquin make them in bronze.

[rbk]

Was thinking as a racer he would go plastic but I didn’t bother researching them when I did mine for the same reasons you give for metal lol so I was t sure anyone made them. I liked BA but found it hard to single source all the sizes I needed in my area, I think they have the same winterizing/zerk fittings as Groco does.

[Jetx]

You might also look at the Foresparseries 93 (OEM) marelon thru-hulls and valves. I believe they're available in either mushroom head or flush head.

[bcboomer]

Having had both Marelon and Trudesign I'd go for Trudesign. Much better product IMHO. They will last as long as the hull.

[john2445]

Why are there 14 holes in the hull?

I would start by glassing in 8 or 10 of them. But that's just me.

[greensail]

Hi ,

I am a ship and yacht surveyor and replaced all my throughhulls with Trudesign glass reinforced nylon from NZ.

They are better than anything else on the market by a long shot. In fact I bought a full set of Groco and then came across the Trudesign. I sold the Groco at a loss to buy the Trudesign.

They don't jamb like the Marlon and don't require stripping to maintain. Advantages are: no electrolysis, no need to bond, won't blow out in a lightening strike, don't jamb up.

Added bonus is they are cheaper. Ball valves are fitted with a support collar and can withstand 500 pounds load.

Bob Green.

[boatpoker]

Originally Posted by greensail

Hi ,
Advantages are: no electrolysis,

Bob Green.

I'm guessing you actually mean "galvanic corrosion" rather than "electrolysis"

"Electrolysis" - is the forced introduction of a current in an electrolyte (water) in order to separate the components. In water this produces Hydrogen and Oxygen.

"Galvanic corrosion" - refers to corrosion damage induced when two dissimilar materials are coupled in a corrosive electrolyte. It occurs when two (or more) dissimilar metals are brought into electrical contact under water. When a galvanic couple forms, one of the metals in the couple becomes the anode and corrodes faster than it would all by itself, while the other becomes the cathode and corrodes slower than it would alone.

[bstreep]

We just replaced all of ours. 16. We asked our surveyor, who is VERY well thought of what we should replace them with. He didn't even hesitate. Bronze and only bronze.

[bcboomer]

Did your surveyor say why he prefers thru hulls that require maintenance, are a potential failure point from galvanic corrosion, and cost more money?

Maybe he just isn't aware of Trudesign.

[Training Wheels]

We also replaced all our thru-hulls with True Design.

[bstreep]

Originally Posted by bcboomer

Did your surveyor say why he prefers thru hulls that require maintenance, are a potential failure point from galvanic corrosion, and cost more money?

Maybe he just isn't aware of Trudesign.

He absolutely is. Just not his preference.

[greensail]

[QUOTE=boatpoker;2667277]I'm guessing you actually mean "galvanic corrosion" rather than "electrolysis"

...Yes you are absolutely correct. I was thinking of electrolytic corrosion as it is a common issue due to stray currents (especially in our marina).