The thread under increasing water tank capacity got me inspired to ask this question. The limiting thing that keeps us having to go to a marina is not water capacity, but waste capacity. We can only go 7-8 days before the red light on the tank monitor comes on. None of the docs we have for that winking little devil tell us exactly how much capacity is left when it comes on . So when it blinks, we head to a marina within a day. We have lots of fresh water capacity, the two stern tanks alone easily make 10-12 days and we can go longer than that on food.
There doesn't seem to be much space in the holding tank area for a bigger tank, and even if one of the correct shape was available a lot of butchery would be needed.
I am toying with the idea of repurposing the bow tank as the holding tank and buying a new water tank to replace the old holding tank. If I do this I am going to use the existing pump out lines and vent rather than make more holes in the deck. I'll be changing all the old black lines to new white ones anyway. Edit: I just thought, why wouldn't I just use the existing fill line for the bow tank pumpout, and the existing vent line for the vent line? Doh!
We regularly carry the bow tank full so I don't see a weight problem that we don't already have, we'll probably end up with less weight up there most of the time.
I'm just wondering if anyone has done this? It seems like it should work, am I missing something why it wouldn't? I don't believe the head outlet would be below the liquid level since the inlet is on top and I'm going to plug the existing outlet (really well plugged!!). Is there going to be some other issue?
Is this nuts? Is there a better option? I am constipated with anticipation for input.
I put in a electro scan system in my boat I use salt water to flush. My brother bought a new Selean Ocean Trawler with 65 gal holding tank and it was not enough for him so he went with a electro scan with a salt tank since he has fresh water flush. I love the system,no more pump out
Bill Miller
S/V Lorraine
Pacific Northwest,Sound Sound
Grapeview,Wa
1990 Mk1
[QUOTE=bstreet;15862]
I'm just wondering if anyone has done this? It seems like it should work, am I missing something why it wouldn't? I don't believe the head outlet would be below the liquid level since the inlet is on top and I'm going to plug the existing outlet (really well plugged!!). Is there going to be some other issue?
Is this nuts? Is there a better option? I am constipated with anticipation for input.[/QUOTE]
I think the height of the tank introduces some difficulty. The fill is also the wrong size, you need a big hose to pump out.
There may be a better option in redirecting with the macerator pump. We're not allowed to pump overboard in the Great Lakes, but the Catalina I have is fitted with a macerator. Seems like it might be possible to use the bow tank as backup, using the macerator to pump from the regular tank into the bow tank when needed.
Greg Jackson
SV Jacqui Marie
2004 C36, MKII
tall rig, wing keel,
Thanks for the ideas. I looked into the waste treating systems but they are 1./really expensive 2./still can't be pumped overboard in our waters on the great lakes, at least I think that's what the myriad rules federally, provincially and municipally boil down to. I'm just not a fan of dumping this stuff into the water, treated or not, even though I know our local municipality "bypasses" in the river whenever there's a heavy rain and the plant can't keep up. Odd how they can "bypass" a million gallons and that's OK, but if I "bypassed" six drops I'd get a $10000 fine. Hypocrisy is alive and well these days. But I digress.
Also looked at the composter types, we compost all we can at home (though not that stuff) so that sounded attractive, but the "liquid handling" part of it is not so much fun. Also pretty expensive.
We do have a macerator, it's locked shut except when I winterize, but I could plumb it to pump from one tank to the other. But I would like to put a 3rd water tank in the space for the current one so that's not the best option.
What about a vented loop in the discharge line from toilet to tank? If that was looped high enough would that not stop any backflow? I think the tank fitting size issues could be worked out, there are guys around here that can weld that type of plastic.
I added a 9 gallon tank several years ago and my boat is 100 miles away-so this is off the top of my head. I put this tank under the settee in front of the galley.I could have put in larger tank but I have heat ducts from my Webasto running thru there. I used a 3 way connector and two valves (one at the end of the exsiting tank and one going into the new tank. By turning valves you can release waste into the new tank and pump out each tank independently. I used PVC valves from Home Depot but I am thinking of changing to a better valve as they are really hard to turn. We also installed a Raritan electric which uses a lot less water.
Chris Hansen
Gunkholer #1889
Lake Mich
Chris, that sounds like a decent idea. I'm trying to picture the plumbing do you have a sketch of how you did it? We have just been using that area for pop and beer but we have lots of room elsewhere for that. Might be the best plan.
Bud, do you have the L-shaped dinette or the U-shaped dinette? Someone on the here website wrote an article (for JibSheet?) about installing a tank under the forward seat of the U-shaped dinette, that gave them another 10 or so gallons holding capacity. That's almost near doubling - but not quite - of the existing Mk II's 14 US gallons usable capacity. (I know it's 14 US gallons because I measured it myself.)
Also, check out the Catalina 350 systems. I don't know if that boat is still being manufactured or not. Their stock installation was an electric Jabsco (I think, but maybe another brand), but with the holding tank placed *above* the toilet. When I first saw that it raised an eyebrow, but haven't heard any more about it. Maybe they have an owners association website??? Anyway, it seems to indicate that with an electric head having a holding tank above the toilet level is do-able.
Larry Brandt
S/V High Flight #2109
Pacific Northwest, PDX-based
2002 C-36 mkII SR/FK M35B
Larry, we have the U shaped dinette. I saw the article on the holding tank under the forward settee but, until Chris posted about his installation, I had ruled out adding another tank. I didn't want to get into putting in another pump out and vent so I thought that using the existing forward water tank would solve that problem. But I like the idea of what Chris has done and that might be the way to go.
Don't have a sketch,but a few more details. I got my tank from Plastic Mart with a 1.5" threaded hole in one end as close to the bottom as possible. This is for both in and out. Also had a .75" threaded hole on the top in the corner nearest the exsisting tank. Tied the vent into the exsisting vent My tank is 16x8x18 with the 1.5" inch hole on the 16 side. I bought a Forespar y conector from Defender. By opening and or closing the two valves you pumpout either tank thru the exsisting deck fitting.
Chris Hansen
Gunkholer #1889
Lk Mich
Thanks Chris, definitely going to look into doing that.
Budd
When you get the installation completed we'd love to see the end result.
We live in Toronto so just a short jaunt to Belleville.
Merry Christmas to everyone on the post and a happy healthy 2013, with lots of great sailing to all.
Brad
2000 Catalina 36
Hull #1915
M35B
TR Fin Keel
"I can teach a man to sail, but I can never teach him why."
Timothy E. Thatcher