[C320-list] water pump won't shut up

[John Frost]

One small point to add. On my boat, if I do run the tank dry, the pump
continues to run with no output even after I refill the tank because it
won't self prime. I have to unscrew the filter and pour some water in to get
it to pump to the set pressure and then turn off.

Happy Sailing!

John
2007 C320MKII
Hull 1118
Guntersville, AL


-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Gary Magnuson
Sent: Saturday, July 21, 2012 4:31 PM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] water pump won't shut up


Good morning Nat,
As I understand our systems, the water pump is a pressure demand pump that
starts when it recognizes a drop in system pressure by opening the faucet
valve. If the tank is dry, then the pump cannot pull water into the piping
to bring the pressure back to the cutoff point.  Since you had to pull the
wire off the back of the panel pump switch, it is possible you have a bad
switch.  To test the panel switch, use a meter or a test lamp across the
contacts in both the open and closed position and see if you have
continuity.  You should read a short when the switch 
is on and an open when the switch is off.   If the readings are the 
same, the switch is bad. But you should be able to still operate the system
if the pump pressure switch is still working.  In order to test that, I
would fill the tank so that the pump has the water it needs to pressurize
the system.  (verify that the pump strainer is clean,  I found mine to be
fouled with plastic shavings and other stuff in the past. When it is
clogged, it will not allow the pump to prime and build the pressure it needs
to satisfy the pressure switch.  With the tank filled and strainer clean,
start the pump again and see if it will prime 
and come back up to pressure.   With the tank filled, it should 
re-pressurize and shut off when the water pressure rebuilds. The sink faucet
valve just is the way we drop the pressure to start the pump and stop the
water flow in order for the pump to rebuild the pressure necessary to
activate the pressure switch.

Sorry for the long winded answer.  I hope it made sense...
Good luck,
Gary Magnuson,
#205   Time A Weigh
On 7/21/2012 11:33 AM, Nat Antler wrote:
> My automatic water pump wouldn't shut off when the sink faucet was closed.
It happened when the water stopped flowing so I assume the tank was empty.
No matter what I did with the faucet valve the pump kept going and the
toggle switch on the panel had no affect so I had to open the panel and pull
the power wire from the back of the switch. Questions: is the switch bad?
does this happened when the tank runs dry? Is the pump bad? Is the control
on the pump that activates it when the water is turned on bad?
>
> Would be most grateful for insights before I start replacing things 
> that may or may not fix the problem. Thanks, Nat Antler 1994-5 320 #161