The freshwater / seawater valve question

[maplemale]

This is probably the first in a plethora of dumb questions I'll be asking since this is my first boat owned (Catalina 27 - 1984).


What is this? It is right below the sink and left of the pump foot-peddle. I'm just guessing it selects freshwater vs. seawater for the sink? If that is the case - which way is which? It will turn clockwise 90 degrees from the pictured position. I've tried both positions and the water appears no different, however i'm in a river bay (Yaquina Bay Oregon). So, both positions are fresh water until I venture across the river bar!


... something I'm disinclined to do until a few things on the boat are fixed / replaced.

[TheOffice]

That's the diverter from the head to either the holding tank or overboard.

Welcome aboard

[maplemale]

Oh!

So... In messing with the positions, did I just dump sewage into the bay!? Wups...

[maplemale]

After further inspection, I'm pretty sure you're wrong.

The tank (underneath the stove & icebox) to the left of my original picture (semi clear plastic tank on port side of boat) has a line coming from it, to the left side of the y-valve (right side on this picture). The top goes to the ft pump and the other side disappears somewhere under v-berth. Guess there's a thru hull somewhere and I haven't found it yet?


I bought the boat with the valve showing flow from the line somewhere under v-berth to the foot pump. I changed it so it appears to be coming from the tank now. Also, not sure what that little plastic 1/4 PVC line is underneath. It's right under the icebox. Takes a few days to leak a little water out. But, it's not connected to the icebox (icebox drain goes to sink drain). So, i'm not sure what that line is for.

[tkeithlu]

Do find those through hulls, and in fact, understand the entire water system, before you venture out. Those are things that can sink your boat, and if you understand them, you have at least a chance of getting to the failed through hull before it's too late.

[maplemale]

Originally Posted by tkeithlu

Do find those through hulls, and in fact, understand the entire water system, before you venture out. Those are things that can sink your boat, and if you understand them, you have at least a chance of getting to the failed through hull before it's too late.

Alright... I'll make that a priority. There's one in the starboard v-berth section that is tied into head and maceration plumbing. The other is in the engine compartment and obviously for cooling. I need to map the entire plumbing system. I guess next marina visit will be doing that.

[tkeithlu]

Sounds like a plan to me. You can inspect them for double hose clamps, operating ball valves, and rotten hose in the process. You'll be way ahead of the average boater when you are finished.

[hellosailor]

maple-

On any boat, the only way to know what's what, especially on a Very Used Boat where several mad genuises may have been improving it, is to peek and poke all over, take notes (pencil & paper are just fine) and puzzle it out.

It is not uncommon to have one fresh water tank under the v-berth, and a second somewhere in the cabin. In which case there's a valve that allows you to select one tank or the other as the water source, connecting to the freshwater pump.

The reason for two tanks is that someone watned to add capacity, or had limited space in any one location, or to balance the boat, or for redundancy. If one tank springs a leak it becomes an inconvenience--not a total disaster.

And that third small line under the ice box? Could be because you never want ice box meltwater draining into the bilge. It will grow crud. But since it is clean cold water, some clever folks plumb it into the sink, with a pump, so you can pump the cold meltware into the sink and use it to keep some sodas or beer cold, without the need to even open the icebox.

I wouldn't mix that into the fresh water supply lines, which it sounds like yours is set up for. We used a separate foot pump to make it easy. But explore...that's the only real way to find out what you've got.

[Skuzzlebutt]

Catalina puts a fresh water tank under the v-berth as well as a second that you've already found.

[Dave22q]

The only way to really know is trace the popes. However, given the location and type of valve (both very similar to my boat) I would put money on a waste diverter valve. Not too many boats are plumbed to offer a choice of fresh vs. salt water for washing or flushing. I've never seen or heard of one and cannot think of a good reason to set this up on water intake. Maybe on a shower but not a sink or toilet.

[Dave22q]

Originally Posted by maplemale

After further inspection, I'm pretty sure you're wrong.

The tank (underneath the stove & icebox) to the left of my original picture (semi clear plastic tank on port side of boat) has a line coming from it, to the left side of the y-valve (right side on this picture). The top goes to the ft pump and the other side disappears somewhere under v-berth. Guess there's a thru hull somewhere and I haven't found it yet?


I bought the boat with the valve showing flow from the line somewhere under v-berth to the foot pump. I changed it so it appears to be coming from the tank now. Also, not sure what that little plastic 1/4 PVC line is underneath. It's right under the icebox. Takes a few days to leak a little water out. But, it's not connected to the icebox (icebox drain goes to sink drain). So, i'm not sure what that line is for.

PVC line probably on refer drain. Your photo very unclear but the usual set up is a 'Y' valve with a selector handle. input hoses from the forward tank under the V berth and the aft tank; the output hose would run through a 'T' to let the foot pump draw water upstream of your pressure pump. The pressure pump output would have one T separating hot from cold. The hot line runs to the heater and another line exits the heater and supplies hot water to the galley sink and the head sink and maybe shower. The cold line skips the heater and runs the same way. Each uses T's to separate water flows. Every connection should be double clamped ate each hose connection. If your photo of the valve was taken in the head I'm sure its a diverter. Catalina made Morgans around that time. My rear water tank is under the aft quarter berth but the boat is larger.

[maplemale]

It's not from the head, it's in the galley. It's definitely a y valve to select forward vs. aft water tank as you said for the sink.


Nothing is double clamped... some of the clamps seem in sketchy shape too. If I'm replacing clamps - should I be upgrading to T-bolt clamps instead of hose clamps? Anything wrong with doing that?

[Dave22q]

Originally Posted by maplemale

It's not from the head, it's in the galley. It's definitely a y valve to select forward vs. aft water tank as you said for the sink.


Nothing is double clamped... some of the clamps seem in sketchy shape too. If I'm replacing clamps - should I be upgrading to T-bolt clamps instead of hose clamps? Anything wrong with doing that?

something not right about this setup. the pressure pump has to be downstream from the tank selector valve. the line to the foot pump has to be upstream from the pressure pump because it cannot pull water through the pump. Therefore there must be a waterline with a T connection to your foot pump then leading forward to the pressure pump and split as I explained. If the Y valve really connects to both water tanks and directly to the foot pump you need a separate network connecting the 2 tanks to a pressure pump to your galley and head faucets. As to clamps, I am not familiar with "T clamps". Hose clamps are fine and it is good practice to use 2 at every connection. Not a safety thing but losing a tank of water because a clamp slipped can be very inconvenient depending on your location. If you have the original Catalina documents, a schematic of your fresh water system should be included. If not you might find one on line or in a Catalina owner's group.

[Jim Cate]

Hose clamps are fine and it is good practice to use 2 at every connection.

For the typical small diameter of freshwater plumbing many fittings are not long enough for double clamping to work. In fact, I've seen quite a few where the second clamp is halfway off the end of the barb and is actually trying to pull the hose off t he fitting!

My own practice is double clamping any fitting that communicates with a throughhull, singles elsewhere. And for t he OP, for small lines the T-head clamps are fine, but likely overkill Use of the non-perforated band clamps is a good idea, for they have a lower failure rate than the common perforated bands.

Jim

[Caleb C]

Hi MapleMale,
We also have this valve in both heads on our Hunter Passage 42.
Our valves switch between fresh/salt water. When we switch to salt, to conserve fresh supply on longer passages, we also have to open our salt thru hull and engage the salt water pump.
Hope this helps.