Fresh water system leak

SG · May 28, 2017

The pump leaking is leaking -- not the tank

The pump recycling is like the product of two things: i) a leak in the hose or fittings; or ii) a bad pressure regulator. The pump cycles when it needs recharge the pressure on the "service" side (i.e. beyond the pump from the supply, or tanks.

The water under that tank may be from a number of sources either related to the routing of lines, a fitting or hose on the tank that causes it to leak when overfilled or underway (heeling, for example), etc. It also could be caused if a fresh water line passes "over it" and water drains down; or it could be caused by a leak allowing rain to get-in.

Does the pump ever get up to pressure (you might have air trapped in the line)? Does the pump ever stop cycling and seem to have satisfied the pressure requirements?

SG · May 28, 2017

What type of pump? Centrifugal or dighaphram?

In my opinion, in order of likelihood:

You have a fawcett, hose, or fitting leaking.

You have a defective pressure switch.

You may have a defective pump (leaky heart valve).

Before you go to sleep for the night or leave the boat, when the pump cycles and turns off, then turn off the circuit breaker to the pump. The next morning you should see if you have pressure by opening a fawcet.

Bill Roosa · May 28, 2017

Pump valves are leaking internally. Pump comes on and pressurizes the system then the water leaks back through the pump valves. Take the pump head apart and clean the mushroom valves.
Bet you use chlorine in your tank. Makes hard and very small crystals that stick to rubber.

SG · May 28, 2017

JWhy: The pressure of a closed system will be the same throughout the system. You won't find the leak by measuring pressure "locally" in each branch line.

I believe if you you have an old PAR reciprocating pump, it's more likely that you would have a leak internally within the pump. It used a diaphragm which could develop and pin hole leak. The Shurflo pumps are less likely to have that problem; but if your check-valve has an issue, maybe.

JWhy: What type of pump? How old is the pump? Have you ever rebuilt it? Do you have a pressure accumulator on the line? (They typically have a bladder which inflates.)

If you let the pump build-up the pressure, you can remove the "supply" line from the pump. Then you should notice water flowing back the wrong direction if that's really the issue.

If you're at a dock, and you leave your pressure water on (with the charger, so you batteries don't get drained) you will likely find the leak somewhere. Have you noticed fresh water in the bilge? (It's time to become "one" with the nooks and crannies. :^))) )

Bill Roosa · May 28, 2017

The amount of water flowing back is not significant enough to measure. The water coming out of the pump fitting will mask the actual backflow water. Also when the pump comes on again you will pump air and cause more problems.

SG · May 28, 2017

Bill, how much water do you have to take out of a faucet before you pump comes on? Do you have an accumulator tank, that makes a difference. If it's that, you'd see a lot more volume than just the inside of the front of the pump.

Again, we don't know which pump he has, but I doubt the volume that will drain out the pump should be that much

If one wants to, one could turn the pump off if you're concerned with some air in the lines. Then leave it open, you will see it continue to drain if the pump is bad (depending on the relative elevation of the pump, for a long or short time).

Before I would do that, I'd try and see if there is a downstream leak. Where Catalina, or whoever put that pump plus the act of stripping it, getting a rebuild kit, or some loose parts, etc. would make it an excercise that might be avoided.

As I said, the first place I'd look for are leaks. Could be in the boat or a wash down or deck shower too. Then I go looking at the pump after that.

Bill Roosa · May 28, 2017

The amount of water that comes out of my faucet is pretty small before the pump comes on. If you have an accumulator then the amount would be much higher though.
I've seen this exact problem almost every other year on my boat. Taking the pump head off is a two fitting and three screw operation (if you have installed it so you can get to the head and not upside down with the motor on top). Takes about 5 minutes to check.

Padrone · May 29, 2017

How about emptying the tank, putting vegetable dye in the tank so you can trace back to the source ?

Stu Jackson · May 29, 2017

Jwhy said:
I'll get the pump information today. And I do get fresh water in the bilge.
This has turned into a real science project, so much to learn about every system.

Once you know what pump you have, then RTFM.

There are very good troubleshooting tips for every fresh (drinking) water pump ever installed on a boat.

I had the same symptoms years ago, traced it down to a leak in one of the lines, replaced all the hoses. If you have a cockpit shower, sometimes they freeze over the winter, easy fix.

Do it methodically.

RTFM.

Tally Ho · May 29, 2017

RTFM?

I am sure I should know what that means....but....

Greg

LeslieTroyer · May 29, 2017

Read the Fine manual

Tally Ho · May 29, 2017

LeslieTroyer said:
Read the Fine manual

Ah....see, I knew I SHOULD know, but alas, reading the manual is never the first thing I do.

Greg

jeepbluetj · Jun 3, 2017

There is no pressure lines in the starboard locker - they're all on the port side of the boat between the head and the galley. Therefore, I think it's unlikely your water in the starboard locker is coming from the pump. I get water in that compartment sometimes after sailing or after filling the water tank (The inspection port on my water tank under the v berth leaks)

A pump will cycle like that if the check valve on the outlet of the pump is bad. I.e. it'll pressurize the lines, the lines depressurize back to the tanks, pump cycles again.