Thru-Hull for Holding Tank Waste

[yvrmarc]

Can someone please suggest a thru-hull petcock valve that can be used for emptying holding tank waste? I can boat 3 miles off-shore and therefore a candidate for emptying a holding tank into the ocean. My main question is: Would a clamshell petcock valve work for this waste removal or would it be subject to clogging up (I do have a macerator pump with the holding tank).? Lastly, where on the hull is the ideal spot to put the waste thru-hull? I assume under the waterline on the side? ? the previous owner keep the holding tank on the swim grid which I am not a fan of ... nor are my fellow moorage neighbours!

Thanks in advance for any insight you can offer

 

[zool]

Re: Thru-Hull for Holding Tank Waste

A seacock it the safe bet for a thruhull, they are pricey tho....mine came with a seacock on the side chine, next to the head, which runs thru a strainer.....

Perko Seacocks Cast Bronze - iboats

theres a special way to install them, where the screws are buried in the glass...

 

[yvrmarc]

Re: Thru-Hull for Holding Tank Waste

Thank you Zool

which runs thru a strainer.....

Is your strainer part of the thru hull? or is it a separate unit on the inside of your hull?

Thanks again

 

[zool]

Re: Thru-Hull for Holding Tank Waste

The strainer on mine is inside the head...its an unmolsted setup but i dont know the hose sequence off hand, as soon as i can, ill trace the whole system and post it back here, maybe you can work your system accordingly.


strainer


seaclock


flush button and mascerator key


holding tank

hope the photos and coming hose routing will help u

 

[yvrmarc]

Re: Thru-Hull for Holding Tank Waste

Thank you very much for taking the time to upload these pictures. This is exactly the visual I needed to reconfigure my setup. I like your setup of having a key switch to operate the macerator pump.

Thank you again

 

[sasto]

Re: Thru-Hull for Holding Tank Waste

What is the strainer for? Anyway, your holding tank seacock needs to be locked in the closed position when your within the 3 mile limit. What I do is remove the handle and store it in a convenient location. The Coast Guard also likes to see a two step process in dumping as zool has. They also like the momentary switch run through an on/off switch.