YF fresh water fill question

[dar636]

Hi - I have the aft main tank in the lazarette that gravity fills the header tank in the guest stateroom, under the bunk. I do have the drawings for the fresh water system.

My question is: When filling the water tank, once the aft tank is full I quit when I hear the vent stop chugging and the gauge reads full. I've always assumed the guest room tank would continue to fill slowly so that the aft tank quantity gauge would be lower when I recheck it some time later. This doesn't happen. The aft tank gauge stays full.

I finally pulled the bedding, looked at the under bunk tank gauge and it reads empty, the tank sounds empty too when smacking the side.

Was it common to decommission that under bunk tank, and if you have the same tanks in a 53 MY or 58 YF, how does the filling system work, as I describe it or some other method?

 

[SKYCHENEY]

There is a valve in the master closet that could be closed. That feeds the mid-stateroom tank.

 

[bigbill]

on my yf the pump pulls from the under bed tank..when filling it goes into the aft tank and also fills the under bed tank at the same time. i never paid any attention to the under bed tank gauge, only the aft tank. when it gets low i fill her back up

 

[meteor64]

On our 1977 YF, the water fill is to the lazarette tank. There is a large hose tying both tanks together. Both are on the same floor level so empty together. Since the half tank is much taller, the side tank stays full until Aft tank is about half full. Then both drain slowly. Fresh water pump is plumbed to side tank. That set up is as per our boat's drawings. Usually, when filling and aft tank overflows, both tank vent flow overboard.

 

[dar636]

Thanks all, I’ll look for that valve, do some more checking and reply back. We’re still out on our winter trip in the San Juan’s.

 

[SEVEN]

While we are on the subject can anyone tell me what is the proper length of the gauge. Mine is about 20” or so and it shows empty at the half way mark. Thanks Rusty

 

[bigbill]

that could be a waterlogged float, pull it and look, maybe just replace the float. if not measure it while its out

 

[cww]

The hose connecting the two tanks together is pretty big. It's bigger than the regular garden hose that you're probably using to fill the tanks. So they just fill up together at the same time when you fill the aft tank. On my boat both vents will usually start discharging water within 30 seconds of each other. If your secondary tank isn't filling, the valve under the floor in the master closet is probably closed.

 

[dar636]

The hose connecting the two tanks together is pretty big. It's bigger than the regular garden hose that you're probably using to fill the tanks. So they just fill up together at the same time when you fill the aft tank. On my boat both vents will usually start discharging water within 30 seconds of each other. If your secondary tank isn't filling, the valve under the floor in the master closet is probably closed.

This is the info I was looking for, the underbunk tank isn't filling - I'm going to look for that valve in the closet. Thank you -

 

[meteor64]

This is the info I was looking for, the underbunk tank isn't filling - I'm going to look for that valve in the closet. Thank you -

Same on our boat. Both vents overflow almost at the same time. We did not have a valve between the two tanks I believe the aft tank float is 24 inches.

 

[dar636]

I spent yesterday opening up everything around the mid stateroom tank so I could see the plumbing. Everything looks intact. Next I’ll pull the gauge out to verify the tank is in fact empty (or not). While I could see the large interconnected fill hose I can’t see a valve under the master closet. It’s carpeted, I pulled everything up in the closet. There is no access panel, if there’s one next to the bed I can’t get to it without ruining the carpet. I don’t think there is…. I can almost see that whole area with a mirror. That said, and since it doesn’t sound like all boats have a valve - I don’t see how that tank wouldn’t fill if that large of a line is open. And I don’t see how the water system would work at all if the tank doesn’t have water in it.???? The plumbing definitely runs from that tank over to the water pumps, there’s no other route. I’m going to have to grab a helper from this point and also try filling while listening to the vent opening which is on the wrong side of the boat the way I’m moored

 

[SEVEN]

Can you measure the length of the gauge. I want to see if mine is correct. It seems to short.

 

[CGHOST4]

On my boat, on the back wall of the master closet under the carpet, there is a removable panel. Behind this panel there is a valve for the center tank. When this valve is closed only water from the aft tank will be used. I have attached some pictures for your review, I hope this helps.


Caesar's Ghost
1980 58YF Hull # 472

 

[SKYCHENEY]

Looks just like mine.

 

[SEVEN]

Looks just like mine.

Mine too

 

[dar636]

Great info - but definitley not like mine. My 90' elbow fitting going into that tank is on the bottom of the tank not the aft end. I can see it with a mirror looking down from the top of the tank between the aft side of the tank and the stateroom wall while lying in the bunk, and there is no valve.

I'll pull the guage out this afternoon to look inside the tank, I will measure it for you Seven.

 

[CGHOST4]

Make a cut out in the floor of the master closet, to give you access to the fitting on the bottom of the tank. There are hose clamps on the water feed hose that will deteriorate over time and you will be glad you had access to them. I am surprised that Hatteras did not provide a way to get at these fittings, unless a previous floor replacement covered the old hatch.


Caesar's Ghost
1980YF Hull#472

 

[dar636]

Hi. Well, the mid tank is indeed full. I loosened the gauge and got a healthy flood of water before getting it out, sorry Seven no measuring the gauge today. I also loosened the vent line, same thing. Water coming out right away. So much for chasing a non problem. I did determine there’s no shut off valve and I’m pretty sure a prior person was into this system ahead of me. The copper vent line was cut and replaced with a rubber hose and while in that access panel outbd of the master closet I found the deck scupper drain hoses had been replaced too. This all started from chasing water that accumulated in the engine room bilge. I thought it could be fresh water as it was only slightly salty. I wanted to make sure I didn’t have a leaking water tank. Pretty much rode that source to ground. I’ll keep looking. At least I know it isn’t the water tank or deck drains. I’ll chalk this up to a win for now. Sideways Pics below of the cut vent line and new deck drain lines, the feed hose to the bottom of the tank showing a dry bilge and the master closet floor and wall. It’s been fun.