Fresh Water System / Pump Not Shutting Down

Tuck · Post by **Tuck** » Tue Jun 15, 2010 7:25 pm

if i'm correct, i have an air leak or something in my fresh water system. problem is,i can't seem to find it.

ever since i've had the boat, it's appeared to take a little while to pressure up and the pump shut off. after looking, i found two water leaks. one under the sink in the head, and the other in the corner of the engine bilge, just up by the bulkhead by the galley...both leaks coming from a connection. with that said however, the system has worked with no real problems, other than the annoying pump up from time to time.

over the winter, it appeared to get a little worse, but again, it still worked.

the other day, for some reason, i turned the water pressure toggle at the lower helm off and went to work. ever since, i can NOT get the system to pressure up...the pump runs constantly.

today, i THINK i got both of the leaks i KNOW of fixed...i tightened them up, and there doesn't appear to be any water coming from the joints now. BUT, the system still will NOT pressurize. the pump runs constantly as it did before. i even checked the connections out in the rear bilge.

could the pump be bad? is there a thingie on the pump which senses the pressure and turns the pump off and could it be badskie?

helpskie!

turtlem1969 · Post by **turtlem1969** » Tue Jun 15, 2010 8:58 pm

More than likely if you cant find any leaks anywhere, it is the the pressure switch, whether you can just replace the switch or if you have to replace the whole thing I dont know.

captainmaniac · Post by **captainmaniac** » Tue Jun 15, 2010 9:44 pm

Are you getting normal water pressure at the taps ? If not, could be the impeller is shot.

Tuck · Post by **Tuck** » Wed Jun 16, 2010 5:58 am

captainmaniac wrote:Are you getting normal water pressure at the taps ? If not, could be the impeller is shot.

well, it's "normal" for what i'm used to...i think. what i mean is, it's always seemed kinda low, especially in the head (if this were the pontifications forum, i could make some cracks about that one. hehe).

so, by impeller being shot, you're basically saying the pump itself could be kaput? (i didn't know water pumps had impellers, but i guess that makes sense.

)

if i have to get a new pump, will an rv pump work, or do i need one specifically for 'marine' use?

g36 · Post by **g36** » Wed Jun 16, 2010 6:48 am

if you want to rule out all possible leaks in your system you could take the hose off the outlet of the pump and attach a very short length of hose that is capped so no water would come out. turn on your pump and see if it turns on and shortly the pressure switch will turn it back off. if it will hold pressure this way then you know that you have a leak in the system somewhere. )most likely somewhere you wont see it) if it doesnt or pulsates then you know you have a pump issue.
if you find that the pump wont turn off and hold pressure this way then you could purchase a rebuild kit for your pump or you could replace it. any 12v pump will work rv/marine as long as it is listed as ignition protected such as below.most are a diaprham type and do not use a impeller. this allows them to run dry with no harm. when replacing mine i watched ebay a got a great deal but if you need it faster then you you might purchase local. have you checked all connections in the system even the one at the tank?

http://www.adventurerv.net/camper-volt- ... osj355gt15

Tuck · Post by **Tuck** » Wed Jun 16, 2010 7:22 am

g36 wrote:if you want to rule out all possible leaks in your system you could take the hose off the outlet of the pump and attach a very short length of hose that is capped so no water would come out. turn on your pump and see if it turns on and shortly the pressure switch will turn it back off. if it will hold pressure this way then you know that you have a leak in the system somewhere. )most likely somewhere you wont see it) if it doesnt or pulsates then you know you have a pump issue.
if you find that the pump wont turn off and hold pressure this way then you could purchase a rebuild kit for your pump or you could replace it. any 12v pump will work rv/marine as long as it is listed as ignition protected such as below.most are a diaprham type and do not use a impeller. this allows them to run dry with no harm. when replacing mine i watched ebay a got a great deal but if you need it faster then you you might purchase local. have you checked all connections in the system even the one at the tank?

http://www.adventurerv.net/camper-volt- ... osj355gt15

great idea. i dunno why i didn't call you to start with

. i'll try that tomorrow (have to go home tonight...it's wednesday, ya know.)

i did check the connections at the pump/tank. there were a couple of fittings that appeared to be loose, and as i said, i think i have them tight, but you know me...

Stripermann2 · Post by **Stripermann2** » Wed Jun 16, 2010 7:45 am

Don't overlook the water heater as a source of a leak. It could be rotted or have a leaking connection. A leak into the bilge could go unnoticed and be a cause of low pressure and pump running continuously.

captainmaniac · Post by **captainmaniac** » Wed Jun 16, 2010 9:26 am

Tuck wrote:
captainmaniac wrote:Are you getting normal water pressure at the taps ? If not, could be the impeller is shot.
well, it's "normal" for what i'm used to...i think. what i mean is, it's always seemed kinda low, especially in the head (if this were the pontifications forum, i could make some cracks about that one. hehe).

so, by impeller being shot, you're basically saying the pump itself could be kaput? (i didn't know water pumps had impellers, but i guess that makes sense. )

If the impeller or seals are worn it can pump up to pressure, but then can lose pressure as water flows backwards past the poor fitting impeller / seals. If they don't make a 'water tight seal', they won't keep the system pressurized without continuous (or at least often) cycling.

randyp · Post by **randyp** » Wed Jun 16, 2010 1:36 pm

I agree with g36. Rule out the pump at the source. If that's ok then keep looking for leaks. The water heater may also be a likely culprit. Also the fittings right at the faucets in head and galley. They can be loose. I basically replumbed the F-26 a few years back and replaced the old pressure switch pump with a flojet VSR pump. They have two sizes, I think. The larger would be good for your system. If you have to replace the pump this is a good choice and RV or Marine retailers sell them. The pump has a sensor which varies the speed of the pump based on demand. So it you open just one tap it will start as soon as it sense pressure drop. If you open the tap more it speeds up, if you open ALL the taps it speeds up even more, etc. I replaced a lot of old water hoses and clamps. The system has been perfect (in spite of my recent screw up on the water heater - previous thread) for over 9 years.

sehord · Post by **sehord** » Wed Jun 16, 2010 10:37 pm

the plug on the discharge side is a true test. You most likely have a worn pump, however you could also have an air leak on your suction side. If the pump has a leak on the intake, it wont pressure up right and will keep the pump running as air can compress as opposed to water and it wont trigger the pressure switch. I just replaced the water pump in my 33' sedan. West marine has a 4 GPM for $99.

davescarrs · Post by **davescarrs** » Fri Jun 18, 2010 10:44 pm

same thing happened to me and i found i needed a new pressure switch. had a little pin hole in it.

Big D · Post by **Big D** » Sat Jun 19, 2010 8:51 pm

If the pump is in good shape, and the switch is deffective, then the pump will try to continue doing its thing and pressurize the system. If the switch is not telling it to shut off, you should hear it labouring as it continues to fight against the pressure in the system. When you turn a faucet on, you should get a good burst of water. If it's not labouring, it's most likely a deffective pump not able to build up enough pressure to trigger the switch.