Water Pressure Pump

[Dockhead]

My water pressure pump failed today.

It is a Jabsco Par Max 4 31620 0094.

It was new only 4 or 5 years ago.

It starting sounding a bit "dry" a few months ago, and I should have paid attention. Then it starting flipping breakers. Then today it locked up.

I took it apart, and ruined clothes when a thick stream of rusty sludge poured out of it.

It seems the eccentric bearing is shot. I can't tell whether this is supposed to be a sealed ball bearing -- maybe the seals are gone -- but it's certainly not sealed now. I cleaned it up and got some grease in it, and it now pumps water again, but does not shut itself off for some reason. Maybe the worn bearing reduces the stroke and it doesn't get up to enough pressure to trip the pressure switch -- I don't know.

I can fix it with a "lower housing kit", which includes the cam bearing.

Or I can just replace it -- it's not all that expensive (about 50% of the European price, in the UK, for God knows what reason).

But shouldn't these last for more than four or five years? Is there a better one? Life on a liveaboard, long-distance cruiser is pretty bleak without running water.

[Omatako]

Personally I think you're lucky to get 5 years. My personal experience puts the durability of these pumps just a little above bilge pump float switches which, for me, rate right next to zero . On most of these pumps the pressure switch is adjustable and quite sensitive - you may try fiddling with that before discarding the pump.

FWIW, I have had best success using SHURflo pumps but even then would consider it great if one lasted 5 years. And I don't live aboard

[jstevens]

Dockside,
Sorry about the premature failure of the pump. It certainly sounds like the failure of a seal.

FWIW I switch to a Max 4 8 years ago after suffering several failures of the newer Jabsco pump with the variable speed motor. Those were real junk. The only other fresh water pump I've used was the old belt drive model, which failed often, but were easy and economical to rebuild.

The Max 4 has been in continuous use as I live aboard.

So I've had good luck with the Max 4, and have no experience with a better pump to recommend.

John

[a64pilot]

Check out the shurflo aqua king II 5.0
I have been very pleased with mine, from a durability perspective none of these pumps will last like a Jabsco diaphragm pump, their downside is noise and the water seems as if it's coming from a pulsating shower head, I keep a spare at all times with the idea of overhauling the busted one and placing it in spares

https://youtu.be/JPMqR5owfv0

Sent from my iPad Pro using Cruisers Sailing Forum

[Dockhead]

Originally Posted by a64pilot

. . . .I keep a spare at all times with the idea of overhauling the busted one and placing it in spares
. . .

Sigh. The voice of wisdom. Why had I not done that, with this vital piece of kit?

[tkeithlu]

The diaphram is torn/ leaking - water should stay on the other side of the diaphram; no rust should be possible. It will pulse if the flow is low enough that the system pressurizes (piping and hoses expand under pressure) stopping the pump, then pressure drops as the water flows, and the pump repressurizes the system. I know I've got a leak somewhere when the pump cuts in every once in awhile when I'm supposedly not using water. I've gotten five years out of Jabscos without trouble, but carry a spare. Strangely, I've gotten 18 months out of one running the toilets and outdoor faucets on my house, which uses cistern water for those jobs, despite pulsing when filling toilets, and no failure in sight.

[RaymondR]

I got rid of the pressurised systems and since I only have a couple of outlets put in separate pumps and switches for each system. Works well, no taps to turn off and foot switches leave both hands free and I get 8-10 years out of the pumps.

[poiu]

Change it for two pumps in parallel, controlled by a standard pressure switch. If one fails, you cope with the low flow - just go onto a rota for showers until the new one or spare part comes. If the pressure switch fails then rig a manual override.

[Dockhead]

Originally Posted by RaymondR

I got rid of the pressurised systems and since I only have a couple of outlets put in separate pumps and switches for each system. Works well, no taps to turn off and foot switches leave both hands free and I get 8-10 years out of the pumps.

An admirable "less is more" approach.

Wouldn't work on my boat, unfortunately. I can just see pumping a foot pump to supply the washing machine with water

[Dockhead]

Originally Posted by poiu

Change it for two pumps in parallel, controlled by a standard pressure switch. If one fails, you cope with the low flow - just go onto a rota for showers until the new one or spare part comes. If the pressure switch fails then rig a manual override.

I thought about that.

Even simpler would be to simply plumb in two pumps with changeover valves and switches.

And even simpler than that would be to simply carry an entire working spare. Why wasn't I doing that?

[bvander]

Originally Posted by Omatako

Personally I think you're lucky to get 5 years. My personal experience puts the durability of these pumps just a little above bilge pump float switches which, for me, rate right next to zero . On most of these pumps the pressure switch is adjustable and quite sensitive - you may try fiddling with that before discarding the pump.

FWIW, I have had best success using SHURflo pumps but even then would consider it great if one lasted 5 years. And I don't live aboard

We have two shurflo pumps, one for FW and another for the anchor/deck was down (salt water) and both being going strong for 12 years now.

[ColdEH]

Throw your anemic 12v pumps over board Dockhead. Get yourself a Headhunter Mach 5 pump and be done with it. You can get them on Ebay cheap. I have been using mine full time for two years . Never any trouble and massive flow and pressure.

You do have to run them an AC 120 or 240 through you inverter . I control mine with a "Square "D" pressure switch and have it set fro 50 to 60 psi, just under were the pump would shut itself off. This over rides the pumps on-board electronics and lets my inverter go into sleep mode .

This pump is so powerful it only runs for 4 seconds to pump the system and accumulator tank up . When running it draws 78 amps off my house batteries and adds up to nothing in the end . The pump is also very easy to bleed and is whisper quiet . Can have two showers running and flush a head with no noticeable pressure drop .

Can you tell I like this pump ?

https://www.youtube.com/watch?v=s8P6uvVtSMw

Cheesy music at the beginning LOL

[Dockhead]

I have a washdown pump in spares, which I never installed.

It's a Johnson WD 5.2, which does 20 liters/min or 5.2 gpm, a bit more than my Par Max. The pressure is higher -- shuts on at 54 psi and off at 70 (5 bars), compared to 40 psi for the Par Max.

I wonder if it would work, or whether it would blow my water system apart? It would be a drop in fit.

[a64pilot]

It will work, one I have is 55 PSI, and I bet the one you have that you can turn the pressure down, or at least I have never seen one you couldn't.
Using a house water pump is an interesting idea, but would need I believe nearly a house sized accumulator to keep it from short cycling.

[ColdEH]

Originally Posted by a64pilot

It will work, one I have is 55 PSI, and I bet the one you have that you can turn the pressure down, or at least I have never seen one you couldn't.
Using a house water pump is an interesting idea, but would need I believe nearly a house sized accumulator to keep it from short cycling.

HeadHunter Pumps are for boats , they have a few that run on 12v .

Yes I do have a big accumulator I think it is 2 Gallons . Been a while since I have seen it .

LOL

Regards