Whale pump help please

[knewboater]

The evenflow auto pump that pumps water to the taps on my boat is pumping on and off every 30 secs. I have checked all the pipes for a leak on the outlet side, but to no avail, the taps work ok when turned on, the filter is clean.
If anyone can help with suggestions for correcting this it will be much appreciated.

 

[Shannoner]

Buy a new one, same thing happened to me recently, the pump eventually failed completely. I got a replacement HERE They were half the price of what I would have paid here in Ireland. They say they can post to a UK address in 2 days, but took a week to get to Ireland, but I saved about 70 Euro, so happy days. Pump looks decent enough but I only installed it last week. It will get a good test this weekend with 8 onboard!
You can email a guy there called Colin, tell him the size of your boat and how many taps you want to run and he will recommend a pump for you, found them very helpful.

 

[Phoenix of Hamble]

Do you have an pressure bottle?

If so, does it have a Schraeder valve on top of it (the sort found on car tyres and some bicycle tyres).... if so, it maybe that you need to re-prime your expansion tank with air, using usually a bicycle pump..... to about 30PSI....

The air is compressed by the water and pump, and eventually creates enough back pressure to stop the pump, but when you open the tap, the pressure encourages an even flow without the pump having to run all the time....

Without this air, the pump can sometimes run far too often and too long....

 

[vyv_cox]

Clean the valves in the pump. Bits of debris (on mine it's copper salts that drop off the suction pipes in the tank, plus sometimes silicone used to seal the tank inspection hatch) get into the valves and prevent them from closing properly. Sometimes a very fine strand of fibreglass or even a hair can do the same. A suction strainer is worthwhile but it doesn't catch everything.

It's a fiddly job and a little daunting the first time but by being methodical you can strip it right down. I do mine in about half an hour now.

 

[jimbaerselman]

These pumps are usually designed to switch on at a low pressure, 10 to 15 psi is typical, and cut out when they reach a higher pressure 30 to 45 psi max.

Nearly all of them work best with an accumulator in circuit - one which, when empty of water pressure, has air pressure in it just above the switch on pressure of the pump.

If your pump is cycling continuously - on-off-on-off-on-off - there's a leak somewhere downstream (even if it's tiny), or you're ingesting aerated water. So check these possibilities out really thoroughly.

So, downstream leak checks you may not have thought of. If you've got one, the accumulator may have a waterside to airside leak, and if you've got hot water, does your calorifier have an internal leak to the engine cooling water? Now the suction side: are the water tanks low? Is attachment to the pump letting air in (grommet gone), do any joins leak air in? Does the pipe have a chafe hole in it?

If all those bits are OK, start to suspect the pressure switches in the pump, a bit of grit inside, or maybe a pump gasket leak. Many pumps dismantle easily and can be cleaned, with troublesome parts being replaced. Sorry, I don't know whether that applies to the whale.

Nice hot weather for this sort of work!

 

[Billjratt]

If you're not getting fresh water in the bilge, the pump is allowing pressure loss back through it's own valves to the supply side. That means a pump-valve overhaul as mentioned above. Forget the accumulator as it only reduces the cycling under normal use. Otherwise only switch it on when needed -especially at night!

 

[donm]

The problem that you describe is quite common and can usually be solved by fitting a surge damper in line. This will accomodate the small pressure differences that are causing your pump to operate in short fits.

 

[knewboater]

Thank you everyone I`ll try all as suggested before buying new. Much appreciated RGH.