I am planning on replacing my 30U’s 58 gallon forward water tank, and my holding tank this Spring, as they are the original aluminum tanks. The holding tank has not presented any issues as of yet, but as it is 38 years old I figured do it now before it has an issue.
The forward water tank has had pin-hole leaks over the years, and I have pulled the tank out, cleaned out the aluminum sand, patched the pin-holes, and put the tank back in place. This has worked well, but it is time for a new tanks from the Nonsuch.org tank program.
Question:
The 1/2" outlet (“drain”) port on the original tank is at the forward end of the tank. Makes it difficult to get the last gallon of the water or anti-freeze out of the tank when winterizing or commissioning, as that part of the tank is slightly ‘up-hill’… my guess is that it is connected this way to help keep sediment/debris away from the “drain” port?
The new tank schematic shows 1/2" drain ports at both the forward and aft ends of the tank, so optional hose attachment… is there a disadvantage to using the aft port instead of the forward port? I am figuring that the aft port attachment point will allow for easier removal of almost all of the water when necessary.
Thoughts/experience?
Oh - and the tank program says 2-3 weeks to receive the ordered tanks… is this fairly accurate? I am trying to hit a window between being away and moving my boat from it’s current location to it’s new Spring/Summer berth in Stamford, CT at the beginning of April.
Thank you,
Peter Grabow
S/V CAKE WALK III
1987 30U 430
Jersey City, NJ
I don’t see a problem with using the aft drain port. I’m assuming that you have a strainer and a large filter like I do that would catch anything. I’ve had troubles with the forward one on my tank due to the sharp turn it makes.
Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
I’m glad I got to read the last two posts about the forward water tank in a N30U.
That will be my next tank replacement when my boat is in the water again this spring.
Right now I’m pulling my old aluminum holding tank and replacing with a tank I bought with the INA Tank Replacement program. It came in about 6 weeks but had to ship from California so not too bad.
Thanks Joe for pointing the way for us.
I use a “Whole House Water Filtration System” from Home Depot, cost about $50-$100, with quick connect fitting to attach dock hose and a short piece of hose to go into deck filler. I clip it onto the life line when filling tanks. This filters the water before it even hits the tank, so I don’t have to clean crud out of my tanks.
I also have a Camco RV carbon filter between the tanks and the water pump, located just under floor boards in the bilge area near head door, to filter again. I change this annually. (see photo)
My forward water tank drains from fitting attached at aft end of tank.
I also installed a “TechEdge iSeries” electronic tank monitor (https://tankedge.com) to keep track of two water tanks and holding tank. I mounted it in a electronic hobby box, then mounted that under head sink so I didn’t have to cut any holes in the woodwork. It doesn’t require any holes to be made in the tank, uses foil strips attached to outside of tank (see photo) and can be calibrated to the odd shaped tanks on the Nonsuch. Very handy when filling water tanks so as not to over fill them, and holding tank too! This can be installed with tanks in place, but would be easier to do before tanks are installed if you are putting in new ones. In Canada it can be purchased online from Marine Outfitters in Ontario, in the USA from the manufacturer in Oregon.
Thank you for all of the responses and information.
Joe - thank you for confirming on the aft drain opening. Yes, I have a strainer and a filter between the tanks and the faucets. The filter is original to the boat, and has replacement wound (English - too many meanings/pronunciations for 1 spelling of a word!) cotton thread cartridges… however the cartridges reduce the water pressure dramatically so I hesitate to use them.
I may upgrade to a different system, such as one that Don Crossley uses (thanks for that info and photos Don!).
Brian - it took 6 weeks for the tank to arrive? I will need to change my timing plan if this is the case as I was trying to time it so they would arrive in a 2 - 3 week window I have to receive them… I appreciate that heads-up!
Also, if you haven’t yet pulled your forward tank, I found it fairly easy to remove (2 people may have made it even easier…). I put a towel on the cabin sole in the forward cabin and when I removed the tank I stood it up vertically on it’s flat end (no attachment points) and then pulled gently on the towel to slide the tank past the folding louvered door that separates the forward cabin from the salon, being careful not to hit the handles for the shower and head… no need to remove the louvered door! It was a close fit, but it works.
Peter Grabow
S/V CAKE WALK III
1987 30U 430
Jersey City, NJ
Peter: I have not noticed any loss of pressure with the whole house cartridge type filter I use that came from Lowe’s Home stores. This one is about 9 or 10 inches.
Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
Peter,
I checked my records and was surprised to find out that my tank delivery actually only took from 11/29/24 when I ordered it until 12/20/24 when it was received so 3 weeks. Sorry for any inconvenience my misstatement may have caused.
Joe - thank you for the filter information… probably time to upgrade my filter system to something more current. Should be an easy enough swap as long as I match the fittings.
Brian - thank you for taking the time to check your records and verify it was only 3 weeks for the delivery. That provides a much more comfortable timing window to place my order and receive the tanks prior to my departure to a new marina (closer to you as a matter of fact).
Peter Grabow
S/V CAKE WALK III
1987 30U 430
Jersey City, NJ (soon to be Stamford, CT)
Following up on the new tanks ordered, and placement of the drain port on the forward 58 gallon tank…
I went to the boat to check the current ports for the potential new ports/location… the aft end of the forward water tank, where I would like to have the new tank’s drain port (instead of located at the forward end as is the original set-up) has perhaps 1/2" (1.25cm) of space between the aft end of the tank and the ‘bulkhead’ that separates the tank compartment from the drawers under the forward berth… unless I can move the tank forward and inch or two and secure it so it doesn’t move, I will need to keep the drain port on the forward end.
I know there are some variations for each of our boats, so always check the layout/spacing prior to ordering openings or parts for your projects!
On the new holding tank, the plan was to add a vent line to the aft end of the tank so there are two vent lines for better air flow through the tank… same issue as above - there is a ‘bulkhead’ separating a beneath the berth storage compartment just aft of the holding tank with perhaps a finger’s width (sorry I don’t know the conversion to metric on this…) of space from the tank to the ‘bulkhead’. I will leave this alone too and continue with a single vent line of the forward end, as the ventilation has not presented an issue in all the years I’ve owned the boat.
Peter Grabow
S/V CAKEWALK III
1987 30U 430
Jersey City , NJ (soon to be Stamford, CT!)
Perhaps you could cut an oval hole in the back of the cabinet between that drawer and your new tank’s drain port? That would give you access to inspect it from time to time (most important after your first filling and after your first sail with the new tank!)
Peter, if you look at my earlier post with the photos, the one that shows the silver foil tape on the end of the tank, is the aft end of my forward water tank under the berth. You can see the space between the end of the tank and the wall of the drawers.
Sorry, but my boat is in winter mode and I got a bunch of stuff piled up on the berth, so I can’t get you a photo of the forward end of the tank at the moment. But as I recall the forward end of the tank is about 4 inches from the forward bulkhead, with an elbow fitting and a hose that leads up to the deck filler.
And if you don’t already know, I believe when installing the the tank fittings use a little 3M 4200 or Sikaflex 291. Don’t use Teflon tape or silicone. At least that is what I was told by a local high-end boat builder.
Hope that helps,
Don
1987 NS30U Breezin’
Vancouver BC
Hi Brian and Don,
Thank you for the additional information.
Brian - I had that same thought, about the access hole through the bulkhead on the aft end of the tank, but I have to wait until I commission the boat this Spring as there are too many items in the way at the moment to analyze the space.
Don - You appear to have more space between that ‘drawers bulkhead’ and the aft end of your tank than is available on CAKE WALK III… I know there is room on the forward end of the tank as I have been able to slide my arm down there to the fitting in the past. I may be able to shift the tank forward enough to use the aft end drain port, if the tank can be properly secured in place… and thank you for confirming about 4200… this is what I planned to use for the fittings.
Best regards,
Peter Grabow
S/V CAKE WALK III
1987 30U 430
Jersey City, NJ
As I am preparing to install the newly received holding and forward water tanks, I have a follow-up question:
What sealant is best for the threads of the male fittings I will install on the tanks?
I have purchased new Marelon fittings as I wasn’t sure I’d be able to remove the old fittings. And the vent openings on the new holding tank are larger than on my original tank.
It appears that 4200, or maybe 5200, was used on the original aluminum tanks and their Marelon fittings… is this acceptable for the new polyethylene tanks and Marelon fittings or is something else the proper way to ensure nothing leaks?
Thank you,
Peter Grabow
S/V CAKE WALK III
1987 30U 430
Jersey City, NJ (moving to Stamford in a month!)
