Water system pump does not shut off

[saltypat]

Hi,

This is our other maintenance problem. Our water system pump (Automatic model 36950-2000) was working this spring. Today it would not shut off(I just filled the tank). It sound like it is running okay, I see the belt turning and the pump oscillating--- water will come out the spigots if I turn them on.

I looked at the pump maintenace site on the web. I'll try opening the spigots first, then turn on the pump, and after water comes out, turn the spigots off and see if the pump shuts off.....
pIf it does not shut off it could be a bad pressure switch or perhaos it needs valve replacement....

Any ideas would be appreciated. The folks who do our maintenace would just simply rip it out and replace it.. as it cost about $300 for the part, that would be a $400-500 repair...

Thanks for any insight,

SaltyPat

[sailingdog]

Umm... who makes the pump??

[btrayfors]

Salty Pat,

You may not want to hear this, but IMHO your Par Jabsco pump #36950-2000 is about the most unreliable one on the market, so you might well think about replacing it....with something else.

If the pump doesn't shut off, it's no doubt a bad pressure switch. But, the pump design itself is really miserable. Over the past 25 years, 17 of them liveaboard, I've tried just about every water pump out there. And, I've worked on lots of others.

My present boat came with four of those pumps for water pressure, bilge, gray water, and spare. I trashed all of them shortly after buying. They look good, but looks in this case are deceptive.

In your stead, I'd replace the pump with a Flojet (not a ShurFlo) fresh water system pump. These are just over $120 these days, or about $175 for the variable speed model. While they've been bought by ITT, so far at least they haven't messed up the original design which is very robust and reliable. I have four of them on my present boat, had four on the previous boat, have installed many on other boats. Great pumps for the price.

Bill

[timebandit]

Are you sure your not pumping water into the bilge??

[tdw]

Originally Posted by btrayfors

In your stead, I'd replace the pump with a Flojet (not a ShurFlo) fresh water system pump. These are just over $120 these days, or about $175 for the variable speed model. While they've been bought by ITT, so far at least they haven't messed up the original design which is very robust and reliable. I have four of them on my present boat, had four on the previous boat, have installed many on other boats. Great pumps for the price.

Bill

You're a splendid chap Bill T .

Am about to do some pump replacing of my own and was about to throw a 'what pump to buy' question into gear and maintenance. Currently a mixture of Shurflo and Jabsco ironically enough.

BTW....what does happen to the liquid if the pump doesn't turn itself off ??

[billyruffn]

A pressure pump that won't shut off is usually either:

- an empty water tank (apparently tanks are full)
- a leak somewhere (look for water in the bilges)
- a bad pressure switch (mentioned above)
- an electrical fault in the pump motor (?)

I've had two Shurflo variable speed pumps that developed the habit of running a lot -- turned out that the seals between the pump housing and the motor had failed and water flooded the motor -- coils / brushes etc. It' wasn't much of leak in terms of volume, but it did cause the pump to cycle on and off frequently as pressure dropped in the system. I wasn't impressed with the Shurflo seals, but the motor was pretty good -- it ran 1/2 full of water.

[btrayfors]

tdw,

Glad this is timely for you. Re: "where does the liquid go?", if you have a leak on the output side of the pump such that pressure can't build, the pump will just go on pumping water through the leak. If, for example, a hose comes loose, you'll pump fresh water right into the bilge.

How do you avoid this?

1. Turn off the FW pump when you leave the boat in case a leak develops while you're gone.

2. Be sure to turn off the hot water heater also, because if a leak develops downstream of the heater the pump will just keep pumping away until all the water is gone, at which time your heating element may well burn out.

3. If you're aboard and you hear the FW pump running continuously...be sure to check it out until you find the fault. Sometimes it's a leak...loose connection. Sometimes it's a bad pressure switch. Sometimes it's a bad diaphram (rarely on FloJet pumps).

One nice thing about the FloJets....the quad diaphram design will run dry without harm.

Bill

[poopdeckpappy]

I'd check for leaks anywhere down the pressure side

Just went threw the same deal with my Shurflo smart sensor. ( which is what I replaced my PAR pump with ) had leaks at both fixtures, (galley and head )they weren't much but enough to keep the pump running at a low level,to the point the pump got way hot.


The pump is so quite it's hard to hear it, and I had no ideaI had a leak until the pumps heat sensor tripped and the pump shut down, once it cooled down enough the restart,I kept my hand on it and felt it running and the search began

[saltypat]

Thanks a lot for all the advice. Tank is full, bilge not getting the water- I imagine it is the pressure switch.....

You have all been a big help.

Best,

SaltyPat