Holding tank pump out design options.

[SSBN506]

I am in the process of designing how I want the holding tank for my challenger 7.4 to work (25 ft boat). It will be a 22 gal tank that will fit under one half of the v-berth. What I haven’t decided yet is where I should run the pump out piping. My wife had told me she spotted a powerboat once where there pump out pipe was fed through the forward hatch when they pumped out. I assume it was coiled up when not in use. Do any of you do this?
If it was airtight this seems like a good option. I won’t have to drill a hole in my deck and have a pipe running up the wall of the vberth?

[AboardIndigo]

Are you or your wife going to take the other half of the v-berth?

I wouldn't do the pumpout through the hatch thing - sounds sketchy. I have no reason for writing that other than the idea sounds wrong.

My pumpout hose runs horizontally under the pan liner, and then up through a hole in the liner vertically tucked into the corner created by the bulkhead and the hull. It could easily be hidden by building a half-box around it or something. Then out through the deck.

[SSBN506]

Originally Posted by AboardIndigo

Are you or your wife going to take the other half of the v-berth?

I wouldn't do the pumpout through the hatch thing - sounds sketchy. I have no reason for writing that other than the idea sounds wrong.

My pumpout hose runs horizontally under the pan liner, and then up through a hole in the liner vertically tucked into the corner created by the bulkhead and the hull. It could easily be hidden by building a half-box around it or something. Then out through the deck.

I should say under one half the the vbirth. I will correct my post to clarify.

[AboardIndigo]

Originally Posted by SSBN506

I should say under one half the the vbirth. I will correct my post to clarify.

Oh, don't do that please. It won't be nearly as funny when I re-read it next week, and then I just have to go and edit my post.

After which time you'll have to edit /\ THAT /\ one.

Followed by me having to come back and edit this one.

I'm getting the sense that this 'post-editing' thing is going to be a long and arduous process...

[sailingdog]

Really bad idea... if the vent line on the holding tank gets clogged, you now have a pressurized hose full of sewage sitting in the v-berth. Is that what you want? Also, if you have it coiled up and then have to run it up through the hatch....have you ever seen what happens when you open the deck fill and the tank has been pressurized... if the deck fill is above an open hatch, guess where the contents end up... that's right, in the cabin.

You really want to have the deck pumpout fitting properly installed so that you can batten down the hatches when pumping out the boat, and if it is pressurized, you can hose the boat down to clean it off...

Originally Posted by SSBN506

I am in the process of designing how I want the holding tank for my challenger 7.4 to work (25 ft boat). It will be a 22 gal tank that will fit under one half of the v-berth. What I haven’t decided yet is where I should run the pump out piping. My wife had told me she spotted a powerboat once where there pump out pipe was fed through the forward hatch when they pumped out. I assume it was coiled up when not in use. Do any of you do this?
If it was airtight this seems like a good option. I won’t have to drill a hole in my deck and have a pipe running up the wall of the vberth?

[wwilson]

Originally Posted by SSBN506

I am in the process of designing how I want the holding tank for my challenger 7.4 to work (25 ft boat). It will be a 22 gal tank that will fit under one half of the v-berth. What I haven’t decided yet is where I should run the pump out piping. My wife had told me she spotted a powerboat once where there pump out pipe was fed through the forward hatch when they pumped out. I assume it was coiled up when not in use. Do any of you do this?
If it was airtight this seems like a good option. I won’t have to drill a hole in my deck and have a pipe running up the wall of the vberth?

SSBN506,

My holding tank is under the V-Berth as well. I second the skepticism on the through the hatch option. That is eventually going to be a mess that you will not want to sleep with. I understand your reluctance to cut a hole in a perfectly good boat, but a deck mount is standard procedure and when the spill or dribble occurs (as it will) a splash of seawater from a bucket will clear up the mess.

You may want to put the pump-out hose & fitting on the opposite side of the beam from the freshwater intake if you have one.

SSBN - Sub Surface Ballistic Nuclear? X-Navy?

[SSBN506]

Originally Posted by sailingdog

Really bad idea... if the vent line on the holding tank gets clogged, you now have a pressurized hose full of sewage sitting in the v-berth. Is that what you want? Also, if you have it coiled up and then have to run it up through the hatch....have you ever seen what happens when you open the deck fill and the tank has been pressurized... if the deck fill is above an open hatch, guess where the contents end up... that's right, in the cabin.

You really want to have the deck pumpout fitting properly installed so that you can batten down the hatches when pumping out the boat, and if it is pressurized, you can hose the boat down to clean it off...

Thanks for the advice. I will have two 3/4 vent lines just to add a bit more info. But the score is now 3 to 0 for not doing it.

[SSBN506]

Originally Posted by wwilson

SSBN506,

My holding tank is under the V-Berth as well. I second the skepticism on the through the hatch option. That is eventually going to be a mess that you will not want to sleep with. I understand your reluctance to cut a hole in a perfectly good boat, but a deck mount is standard procedure and when the spill or dribble occurs (as it will) a splash of seawater from a bucket will clear up the mess.

You may want to put the pump-out hose & fitting on the opposite side of the beam from the freshwater intake if you have one.

SSBN - Sub Surface Ballistic Nuclear? X-Navy?

Thanks another point I hadn't considered. This is why I love sailnet.

You have the SSBN correct but I am not navy. Just been a sub buff my entire life and used the SSBN nick back in the bbs days then mirc and now internet forums. It is only picked up on this forum no other forum has anyone noticed in 17+ years. Back in the day I could use just SSBN I didn't have to add numbers to it. Sometimes people ask me what sub had the number designation of 506? Again only on this site do people have the understanding to notice it is not a valid ballistic missile sub designation.

[sailingdog]

glad to help. btw, run the vent lines as straight and short as possible

[Architeuthis]

Sure you can make it work by running the hose through the hatch.

It means having two people, one at pump one at boat and a hose with shut off valves on each end.

Then connect boat hose to dock hose, open both valves on boat hose (and whatever valves are required dockside), pump on, pump hazardous waste until tank empty. Shut off pump, reverse pump to empty hoses as much as can be, close topside valve (boat hose) while pump in reverse, hold hose connection up so waste will not be at hose connection, close dockside hose valve, crack then disconnect fitting, continue holding both hoses up, shut off pump. Use pump person to cap dockside hose, wipe down the outside of hose as required, return to rack ready for next use.

While holding boat hose up, crack valve to empty remaining contents of hose into holding tank, close and lock valve (you need a lock so valve cannot open when being moved around), wipe clean, install cap, secure hose end on deck so it does not fall down hatch. Go to other end of hose while holding it so waste drains out of hose down to holding tank and close hose valve at holding tank and lock, with rag in hand disconnect hose, hold open end up, wipe clean, install cap.

Wipe down hose, place back in hose bag. Cap holding tank fitting, wipe and clean top of tank, store hose bag on top of tank. Dispose of all rags, and if done properly there should be no need to wash hands...but do so anyway!

Easy, peasy.

If you can develop and test such a procedure, and your other person is the type that can do such tasks, repeating back instructions, double checking each step, then it can be done and done right hundreds of times.


Of course miss one step, one time, and the expense of a proper install will seem insignificant, particularly after buying all the extra parts and hose needed.