Through-hull

[Jim Carter]

I have to get a through-hull valve replaced and I'm trying to figure out the size. From looking at the manual this may have been added by a PO. It's located in the hanging closet between the chart table and the head. Or is this standard and just not in my nanual? I have a two position valve that redirects waste from the tank to this through-hull. It's much larger than the others on my boat, if it's standard anyone know the size?

[Dave Spencer]

Jim,
With boats as old as some of ours, it's hard to say if something is "standard".  However, I too have a through hull fitting in my hanging locker.  It is semi-permanently capped off and its obvious intent is to accommodate a blackwater waste dump valve.  I'm in the Great Lakes and don't discharge overboard so it is capped.  I examined my capped through hull last week as I'm considering adding a macerator pump for a future trip to the Bahamas.  I'm quite certain it is an 1 1/2" through hull.  (i.e. it would accommodate a 1 1/2" valve).  Yours may be different.

[Jim Carter]

Yeah I have a 1.5 hooked up to the macerator now, it's smaller than the one in my hanging locker, this one is set up to discharge waste straight overboard and seems much larger.

[Dave Spencer]

I have a picture of my capped through hull but it's not great and there's no reference so it's hard to judge the size.  Attached anyway.
You may want to measure the major diameter of the through hull (across the threads) and compare it to industry standards thereby working backwards to figure out what you have. 
Here's a link to Apollo through hulls with dimensions.  https://www.defender.com/pdf/TS_65_xx7.pdf
And here's a link to NPSM thread dimensions.  The major diameter for 1 1/2" straight pipe thread (NPSM) is 48.26mm (1.9")  https://www.gewinde-normen.de/en/npsm-pipe-thread.html
Let us know what you find.

[Jim Carter]

Dave you may be right, mine might be a 1 1/2 as well, the others like from the macerator are smaller, and I post a picture to save my life here. Thanks for your input.

[Stu Jackson]

D>>>>>>>>>>>>>>>>>>>>>>>>>>>
.........................and I post a picture to save my life here. >>>>>>>>>>>>>>>

Jim,

I assume you meant you can't.

Here's how (third choice down in the 101 Topics):

Posting and RESIZING Photos 101  http://c34.org/bbs/index.php/topic,3701.0.html

[Jim Carter]

Stu yep meant can't. All of the photos were under 500kb. So I don't know what is going on.