Fresh Water System Problems


afratki

afratki

Member
I'm having problems with the fresh water system on our 2005 370 SS that is NOT a single fill system. It has separate inlets for filling the onboard fresh water tank and for hooking up to city water.

Last year I started noticing air in the system while using the onboard pump that wouldn't bleed out no matter how long I let the faucet run. And sometimes the pump would continue to run after shutting off the faucet presumably because it couldn't build pressure with air in the system. Never noticed any water leaking into the bilge and everything working fine when I was hooked to city water. For various reasons I never gave any serious time to figure out what was causing this problem.

Fast forward to last weekend, I'm at a marina (hooked to city water) and on the third day of a four day stay we came back to the boat and there's no water at any faucet. Of course I check the dock hookup and plenty of water there. I turn on the fresh water pump figuring I'd use the onboard system and pump doesn't run and still no water. After spending 30 minutes turning the dock hose bib on/off, hooking and unhooking the hose, turning the fresh water pump on/off, etc. I can't get any water to work on the boat. We make due the rest of the stay with no onboard water.

Go to the boat today to look into this. First thing I do is open the city hookup inlet to hookup the hose and I hear a pressure release sound that I've never heard before when opening it. I try the city water hookup and have water. I try the fresh water pump and it works (still spitting air when using though). I'm starting to think that what ever mechanism that seals off the city hookup when the pump is used and visa versa is malfunctioning. Does anyone know where this is located? Is it built into the city water inlet and is there a rebuild kit for it?
 
I think I'd start by checking the switch to select whether you are using dock water/fill tank/water pump, see if it works properly, About the water pressure, did you check the accumulator that keeps the pressure constant between pump cycles?
 
There is no switch per se, the city water inlet lets water in when a hose with pressure is attached and seals the inlet off to the rest of the system when there isn't. I've ordered a new city water inlet (figured for $40 it's pretty cheap and the old one was getting pitted) and will install it this weekend. I'll circle back next week to let you know how it goes.
 
Last edited:
I'm not real familiar with your fill system, but a few thoughts.
1. JaRod has a good point, I'm pretty sure the fresh water inlet is both a regulator and a check valve, it may be hanging up.
2. If there is air in the system, with the onboard pump, more than likely it is a leak on the suction side of the pump. I'd start there, inspecting the inlet filter, and as many connections as you can get to. It doesn't take much, as nature abhors a vacuum.
 
Not to hijack his thread but I too have fresh water issues. I definitely have air in my lines, water is sputtering out every faucet and it doesn't clear up no matter how long i run it out. Water pump runs constantly even after shutting all faucets. Filter is clear on suction side, no visible leaks in the bilge piping nor any leaks in the kitchen/bathroom area.

I have never used my city water inlet ever, but do you think that could be leaking air in the line?
 
Has everyone checked the in-line water filter in front of the pump. It sounds like each of you have a clogged filter. It is a small, clear plastic filter that has a small metal screen inside. It has a top and bottom section that screws together. Pull apart the filter and clean the metal screen.

Also, you may want to remove and clean the aerators on each faucet. They can get clogged too and the symptoms are the same.
 
Last edited:
Good point, I have checked both, both clear. But neither being blocked would make my pump run constantly?
 
pump running constantly means it is not building pressure. Is there a leak somewhere or possibly a valve open somewhere? Transom Shower? Regular Shower? Toilet? Hot Water Tank drain valve?
 
Make sure your vent on your fresh water tank is clear. Sometimes spiders can plug it up and the pump can’t create suck with not venting

mark
 
MrCIG said:
Make sure your vent on your fresh water tank is clear. Sometimes spiders can plug it up and the pump can’t create suck with not venting

mark
Click to expand...

Thanks for that advice, hadn't thought of that. I will check this weekend.



Sent from my iPhone using Tapatalk
 
Circling back will the resolution. Pretty much by process of elimination, I replaced the fresh water pump and fixed the problem. I guess pump impeller and/or housing was causing the cavitation.



Sent using Tapatalk
 
You must log in or register to reply here.
Back
Top