Fresh water pump
- 1992330aftcabin
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Fresh water pump
I thought I would share this with you. My fresh water pump (Sure flow pump) was coming on for a moment then shut off, my first thought was I have a leak in the system. I spent several hours looking for a leak no leak found. I didn’t like listening to the pump run so I turned the pump off and ran shore water pressure, the next day I had water coming out of the fresh water tank vent. I scratched my head for a few and realized there’s only 1 check valve in the system ( hot water tank cold water inlet). I researched the fresh water pump and it has a internet check valve that was leaking and filling the water tank. I replaced the pump and both problems are gone. Hope this helps someone in the future.
- mjk1040
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Re: Fresh water pump
Pro active issues are always a good idea!
Mike
I'd Rather Be Boating!
1989 Sea Ray Seville
1986 Carver Mariner 32'
1990's Thompson 22' Cuddy Cabin
1990's 4Winns 245 Vista Cruiser
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I'd Rather Be Boating!
1989 Sea Ray Seville
1986 Carver Mariner 32'
1990's Thompson 22' Cuddy Cabin
1990's 4Winns 245 Vista Cruiser
1980's Thompson 19' Open Bow
-
Viper
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Re: Fresh water pump
Ya it's one of the common pump failures. Every pump will have an and outlet/reverse flow check valve. Some accomplish that right at the outlet port and others rely on bellows contact with internal port. Debris is usually the cause of the failure or chemicals like bleach, or high alcohol levels in cheap plumbing antifreeze. Oh Oh, there's that cheap plumbing antifreeze subject again 
- cmlrfp
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Re: Fresh water pump
Question on using dock water to pressurize your boat so you don't use the house tank..... I notice that when connected to dock domestic water supply my fresh water holding still goes down!!!! Is this normal or is there an issue with a check valve or something
2012 41CMY
Thanks all
RP
2012 41CMY
Thanks all
RP
- tomschauer
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- Midnightsun
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- km1125
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Re: Fresh water pump
Yes, like others have mentioned, kill the potable water pump at the breaker. Your pump pressure is likely set higher than the city water pressure, just like mine. If you want that extra pressure for certain uses (like a nice shower or a good deck washdown) then kick the pump on and use up some of the tank water.cmlrfp wrote:Question on using dock water to pressurize your boat so you don't use the house tank..... I notice that when connected to dock domestic water supply my fresh water holding still goes down!!!! Is this normal or is there an issue with a check valve or something
2012 41CMY
Thanks all
RP
Last edited by km1125 on October 17th, 2019, 6:20 pm, edited 1 time in total.
- 1992330aftcabin
- Deck Hand

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Re: Fresh water pump
As stated in my original post, the water pump was coming on. So I turned off the pump and ran off city water then I had water coming out of the vent. At the end of the day I replaced my pump and resolved my issues.