Jabsco Parmax 4 fresh water pump - Prease help preserve my sanity ............... !!!!

CPD

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I have just replaced a (very old - 15+yrs) parmax unit with a parmax 4 HD. The system is extremely simple - tank to pump to two taps. The new pump insists on pumping (less than a second) every 5 secnds or so. This can only indicate a leak in the pipework somewhere no ??. The old pump was as good as gold - until it died of course :) ...............
 
I have just replaced a (very old - 15+yrs) parmax unit with a parmax 4 HD. The system is extremely simple - tank to pump to two taps. The new pump insists on pumping (less than a second) every 5 secnds or so. This can only indicate a leak in the pipework somewhere no ??. The old pump was as good as gold - until it died of course :) ...............
Or debris in the pump valves preventing them closing properly and therefore allowing water to leak backwards through the pump.
 
Water leaking back through the pump valves, either muck or faulty pump. Parmax 4 is not a good quality pump, look at where it is made.
Accumulator yes or no is not relevant to your problem.
I replaced my Jabsco with a Shurflo Aqua King II last autumn.

It worked very well until last week and the tech help at Lee San who supplied it asked that I check the accumulator pressure as part of the fault finding procedure.

If the accumulator is leaking air slowly then the pump will cycle as it attempts to maintain pressure in the pipes downstream of the pump.

Anyhow, after removing the pump, I discovered the pressure relay contacts measured 400 ohms when closed which is restricting current to the SPST relay that feeds the motor. Different issue to the OP but the accumulator pressure was relevant to the flow and bypass pressure settings in my set up and was ticked off as part of the general fault finding procedure.

Vyv offers good advice about the filter. Our boat is still trapping blue plastic swarf in the filter from the lack of care or clean up after Beneteau drilled the tanks for pipe fittings almost 10 years ago :eek:
 
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Very timely - on Sunday night I ordered a new Shurflo Aqua King II to replace my slightly leaking Aqua King Junior that's presumably ~ 20 years old, and bought an in-line filter to attach to it given the current lack of any filtration. At the weekend I also installed an isolation valve in the freshwater supply pipework, given there was no way of shutting off the water feed to the pump, making any maintenance a right pain.

Wonkywinch - did your Aqua King need replacing if the pressure relay was faulty?
 
Wonkywinch - did your Aqua King need replacing if the pressure relay was faulty?
It's on it's way back to Lee San at the moment. They wanted it back rather than take my word and just supply the microswitch, but that's understandable.

The Shurflo was supplied with the microswitch already in series with the pump, so all it needed was +/- 12v to then run when pressure was low. The problem I had was Beneteau have three wires going to the pump, the third a signal wire back to the main panel to indicate pump was running.

As an engineer, I didn't like the thought of wiring a big inductor like the 10 amp motor being switched with a microswitch so I connected it up through the existing automotive type relay so the built in microswitch only powers the relay coil, not the dirty great motor.
 
It's on it's way back to Lee San at the moment. They wanted it back rather than take my word and just supply the microswitch, but that's understandable.

The Shurflo was supplied with the microswitch already in series with the pump, so all it needed was +/- 12v to then run when pressure was low. The problem I had was Beneteau have three wires going to the pump, the third a signal wire back to the main panel to indicate pump was running.

As an engineer, I didn't like the thought of wiring a big inductor like the 10 amp motor being switched with a microswitch so I connected it up through the existing automotive type relay so the built in microswitch only powers the relay coil, not the dirty great motor.
Super, thanks for the detail - completely agreed on the relay! You hear very mixed feedback on the Shurflow units, but given it's predecessor seems to have lasted a good number of years, I just replaced like for like for simplicity.
 
Removed my old Shurflo this afternoon and replaced with a new one on very good price from Chas Newans. The old one appears to be the original unit given the boat is a 2000 build, labelled as manufactured in March 1999, so I can't complain after ~25 years of service! Let's just hope the new one lasts as long...
 

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Our pump had very low flow for a while before stopping. I assumed it was the pump but couldn't find a problem with it. Checked all pipes and no blockages. Finally removed the manifold just before the pump. It had a little ball of plastic at the output end. All perfect after removing it. The black plastic ball unravelled into a thin tube with some holes. It must have been a liner, just a tube with holes where the valves led off to the water tanks. The manifold was clean and smooth inside. Manifold and liner were made of very similar black plastic. I only use the water for washing and odd coffee so didn't bother buying a new manifold.

Quite a tricky fault to diagnose. OP's sounds simpler as it's either water leaking out after it or valves/diaphragm leaking as the most obvious faults.
 
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