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BlueStringPudding

Replacing a water pump

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Today I decide to find the source of my never-turning-off water pump. It wasn't difficult to find ūü§£. The Jabsco pump is wazzing¬†out water from its snoot (technical name unknown obvs), whether¬†there is power to the pump or not. So for now I've isolated the water supply between the tank and pump, till I can replace the pump. But I've a few questions:

1. Assuming this type of Jabsco pump is still made (it could be as old as the boat - it's a 1997 Black Prince ex-hire boat), is there any reason not to replace the pump like-for-like? Or should I go for something different and if so what and why?

2. Can I get away with just bolting a new pump onto the metal mounting bracket that's under the old one, or will I need to replace or change any of the stuff around it?

3. Peering up towards the water tank beyond the front steel bulkhead (the tank is steel, pretty inaccessible and supposedly integral to the hull) there's clearly some rust around it and some wet wood. Feeling around the fittings that come out of the tank, they seem dry and the tank feels like it has condensation on it (I can only reach a corner of it to check) but there is no apparent leak. Could the wet wood and bow rust be related to the leaking water pump even though they are forward of the pump? Or just condensation? And what if anything should I do about that rust and that wet corner of wood (other than run up and down screaming)?

 

If I can post a video clip here I will, if not I'll just put some photos below. 

 

Thanks all ūüėä

 

Edited to add: Dagnabbit - the forum is telling me even the photos are too big to upload. While I try to work out how to shrink them, I'll post them on the CWDF Facebook page then below.

For Facebook users, here's a link to the photos and video: https://m.facebook.com/groups/707309872616701/permalink/4069905659690422/

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Edited by BlueStringPudding
Reduced photo size to upload them, video only on Facebook though

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29 minutes ago, BlueStringPudding said:

1. Assuming this type of Jabsco pump is still made (it could be as old as the boat - it's a 1997 Black Prince ex-hire boat), is there any reason not to replace the pump like-for-like? Or should I go for something different and if so what and why?

 

Go for similar pressure and flow rate assuming it all worked fine before it died. Pressure is important if you have a calorifier as you don't want the new pump pressure to exceed the lift value of the pressure relief valve (PRV). If you have an instantaneous gas heater, then going for significantly different pump might cause problems if the heater decides it isn't happy with pressure, or flow rate. If the deceased one was 23 years old it did very well. I seem to kill them after around four!

29 minutes ago, BlueStringPudding said:

2. Can I get away with just bolting a new pump onto the metal mounting bracket that's under the old one, or will I need to replace or change any of the stuff around it?

Don't know without seeing it and I don't do any of that TwitFace stuff. You'll likely need to do some plumbing and fabrication, but not anything too serious.

 

29 minutes ago, BlueStringPudding said:

3. Peering up towards the water tank beyond the front steel bulkhead (the tank is steel, pretty inaccessible and supposedly integral to the hull) there's clearly some rust around it and some wet wood. Feeling around the fittings that come out of the tank, they seem dry and the tank feels like it has condensation on it (I can only reach a corner of it to check) but there is no apparent leak. Could the wet wood and bow rust be related to the leaking water pump even though they are forward of the pump? Or just condensation? And what if anything should I do about that rust and that wet corner of wood (other than run up and down screaming)?

Probably condensation. Unlikely to be any relationship with the pump leaking. The wet wood is a little more concerning. Is it soft to the touch?

 

Jen

Edited by Jen-in-Wellies
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Any pump of similar cut put pressure will do the job but Jabsco are one of the more reliable makes.

 

New pumps normally come with a new metal foot with rubber anti-vibration blocks. you do not screw these blocks down tight so normally you would just undo the four screws and lift the whole lot out.

 

Judging by my boat I suspect its condensation

 

 

Edited by Tony Brooks
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6 minutes ago, Jen-in-Wellies said:

 

Go for similar pressure and flow rate assuming it all worked fine before it died. Pressure is important if you have a calorifier as you don't want the new pump pressure to exceed the lift value of the pressure relief valve (PRV). If you have an instantaneous gas heater, then going for significantly different pump might cause problems if the heater decides it isn't happy with pressure, or flow rate. If the deceased one was 23 years old it did very well. I seem to kill them after around four!

Don't know without seeing it and I don't do any of that TwitFace stuff. You'll likely need to do some plumbing and fabrication, but not anything too serious.

 

Probably condensation. Unlikely to be any relationship with the pump leaking. The wet wood is a little more concerning. Is it soft to the touch?

 

Jen

Thanks Jen. I've uploaded photos now

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Like-for-like replacement is always far easier than fitting "something else".

 

As my boss used to say, decades ago, "Give it a KISS"*.

 

I see no reason at all why you shouldn't use a new Jabsco pump. After all is said and done, the old one seems to have lasted 23 years!.

 

* Keep It Simple, Stupid.

 

 

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By the way, thanks for posting on this subject - you have reminded me to check my own Jabsco pump, which I dismantled and cleaned when I was repainting the water tank, what seems like aeons ago. Mine isn't bolted down, by the way - it sits on a thick rubber mat to reduce vibration transmission at audible frequencies. Otherwise known as noise.

 

 

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That model is still available and has quick release fittings, just pull back the tabs behind the black adaptors to remove/insert.

 

FWIW it's a good idea to remove the old O rings from the adaptors and replace them with those included with the new ones.  I didn't and ended up disturbing joints that led to having to plumb two new sections.  It sticks in my mind because I needed 4in of pipe and had to buy 3m of each (15 & 22m), one part was incorrect so I had to make two trips to Screwfix and a wet vac required to remove the water it dumped while I was in the car!

 

Xylem are the main agent for Jabasco.

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3 minutes ago, GRLMK38 said:

That model is still available and has quick release fittings, just pull back the tabs behind the black adaptors to remove/insert.

 

FWIW it's a good idea to remove the old O rings from the adaptors and replace them with those included with the new ones.  I didn't and ended up disturbing joints that led to having to plumb two new sections.  It sticks in my mind because I needed 4in of pipe and had to buy 3m of each (15 & 22m), one part was incorrect so I had to make two trips to Screwfix and a wet vac required to remove the water it dumped while I was in the car!

 

Xylem are the main agent for Jabasco.

Interestingly, I can't actually find that model on the Jabsco website. Do you know where you've seen it, please?

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20 minutes ago, BlueStringPudding said:

Interestingly, I can't actually find that model on the Jabsco website. Do you know where you've seen it, please?

Jabasco have a habit of changing part numbers so the equivalent is 31620-0292.

 

https://www.pumpvendor.com/media/jabsco/Jabsco_31595_31600_31620_31630_series.pdf

 

https://www.jabscoshop.com/marine/pumps/pressurised-fresh-water-pumps/31620-0292-par-max-4-pressure-controlled-pump.htm

 

Data sheet for original https://www.pumpvendor.com/media/jabsco/Jabsco_30600_30620_30630_series.pdf

Edited by GRLMK38
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The black threaded port adapters will pull¬†out of the old pump¬†when you release the slide clips. A new ParMax will come with similar snap-in adapters, with luck they will be the same fitting on the pump side and the old ones will go straight in. Worst case you may have to use the threaded adapters from the new pump and move the tap connectors over (the ‚Äútap connectors‚ÄĚ are the brass nuts where the black pump adapters meet the grey pipe). The clips on your old ParMax look the same as the ones on my Shurflo shower pump (in fact the whole business end of the pump does), and as far as I recall the adapters are interchangeable.

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16 minutes ago, BlueStringPudding said:

Thanks. It's got a different snoot on it to my old one. Is that just a cosmetic difference, do you think?

Just a change to the cable entry design by the looks of it¬† You appear to have plenty of space available so the "tweaked snoot" ( ūüėĬ† ) should not cause you any issues.

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4 hours ago, David Mack said:

Can you replace just the pressure switch?

I don't know. I don't know what one is or how to change it. And if I go to all that trouble and that wasn't what was wrong with it, it's a lot of hassle and a longer time to go without running water. 

Spares Marine seem to do a pressure switch for this model. But also a low pressure switch. And a micro switch... I don't know which is needed, if I'm capable of replacing it, and even if that part is definitely the problem. Did you see the video? That shows most closely where the water appears to be leaking from. Assuming there's not a crack or something failed elsewhere contributing to the leak.

I need the¬†simplest, quickest solution for someone with limited physical ability - whether that solution means replacing a part or replacing the whole thing.¬†¬†ūü§Ē

Edited by BlueStringPudding

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57 minutes ago, BlueStringPudding said:

I don't know. I don't know what one is or how to change it. And if I go to all that trouble and that wasn't what was wrong with it, it's a lot of hassle and a longer time to go without running water. 

Spares Marine seem to do a pressure switch for this model. But also a low pressure switch. And a micro switch... I don't know which is needed, if I'm capable of replacing it, and even if that part is definitely the problem. Did you see the video? That shows most closely where the water appears to be leaking from. Assuming there's not a crack or something failed elsewhere contributing to the leak.

I need the¬†simplest, quickest solution for someone with limited physical ability - whether that solution means replacing a part or replacing the whole thing.¬†¬†ūü§Ē

The switch is the bit with the 20psi printed on it. It is held on by two screws. Turn the water and power off, remove the two screws and pull the switch housing out.

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Thanks. I won't be detaching anything just yet until I can work out how to get any replacement part or pump sent to me when I technically don't have a postal address till Christmas. But in terms of ordering the part, (assuming I don't just think: "B*gger it, I'll blow ¬£200 on a whole new pump instead") would the part¬†be called a Pressure Switch or a Low Pressure Switch or a Micro Switch? They seem to be the three pump parts available online with the word switch in the name ūü§Ē

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17 minutes ago, BlueStringPudding said:

Thanks. I won't be detaching anything just yet until I can work out how to get any replacement part or pump sent to me when I technically don't have a postal address till Christmas. But in terms of ordering the part, (assuming I don't just think: "B*gger it, I'll blow ¬£200 on a whole new pump instead") would the part¬†be called a Pressure Switch or a Low Pressure Switch or a Micro Switch? They seem to be the three pump parts available online with the word switch in the name ūü§Ē

Of course it comes down to availability of funds but from what I can see you could be in for nearly £100 for parts for the 3 you mention (and a bit more if you decide to do the diaphragm at the same time) plus whatever you value your time as.  Alternatively you can amortise £200 over the next 23 years and then replacement becomes a no brainer.  OK 23 years is optimistic but it should do 10 and you get warranty on a new one.

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19 hours ago, GRLMK38 said:

I notice there are three spec differences I can see at first glance between the two pumps, so it doesn't seem to be the same thing just with a changed part number after all (fuse size, GPM/LPM and PSI are all slightly different) ūü§Ē The question is whether the differences will¬†be of any consequence to my boat's original plumbing/accumulator/old calorifier/original electrical wiring/fuses/later addition by a previous owner of an isolation switch,¬†¬†etc?

 

New suggested model: Jabsco 31620-0292

Fuse Size: 15(amp)

Output: 16 litres/minute (3.5 gallons/minute) open flow

PRESSURE SWITCH - cuts in at 0.7bar (10psi) - cuts out at 1.7bar (25psi)

 

 

My current model: Jabsco 30620-0292:

 

Jabsco Par Max 4  3.8 GPM/14.4LPM
20psi automatic water pressure pump

10A fuse breaker
 

What do you guys and gals think?

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25 minutes ago, BlueStringPudding said:

PRESSURE SWITCH - cuts in at 0.7bar (10psi) - cuts out at 1.7bar (25psi)

Do you have a calorifier? If so, what is the opening pressure on the PRV? If it is the common type, it should be written on the red knob. Mine says 3 bar, which is comfortably above the 1.7 bar max of the pump you are looking at. Almost certainly will be OK, but just check. Also check the fuse that is currently used for the water pump. May need increasing in size to 15A. What is the wire size and run length from batteries to pump, to make sure it can handle the max current. Running current will be a lot less, around 4 or 5A. A picture of the added isolation switch would be good. Hopefully it will be a nice meaty one, able to handle the current.

Jen

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48 minutes ago, Jen-in-Wellies said:

Do you have a calorifier? If so, what is the opening pressure on the PRV? If it is the common type, it should be written on the red knob. Mine says 3 bar, which is comfortably above the 1.7 bar max of the pump you are looking at. Almost certainly will be OK, but just check. Also check the fuse that is currently used for the water pump. May need increasing in size to 15A. What is the wire size and run length from batteries to pump, to make sure it can handle the max current. Running current will be a lot less, around 4 or 5A. A picture of the added isolation switch would be good. Hopefully it will be a nice meaty one, able to handle the current.

Jen

Thanks for the advice. I would love to be able to answer all those questions, but none of those things are easily (or in some cases, at all) accessible and the fuses aren't even labelled. I've no idea what Black Prince used cable-wise when they built this boat. I can only see the bit of cable in the photo above, that attaches directly to the pump,¬†but I don't know what gauge that cable is or if it's the same gauge all the way to the fuse box 50+ feet away. The wiring is all built in behind walls and built-in furniture, and inaccessible. The isolation switch cable (a later addition) is thin, but maybe that doesn't matter.¬†¬†Judging by how dim some but not all of the lighting is, Black Prince used whatever cable was lying around ūü§Ē¬†

I've already pulled to pieces the kitchen to access the water pump and can't put that back together until it's resolved. To do the same to the back cabin (the only other living space) while I'm trying to live aboard, just to try and see a knob on the calorifier seems a bit fruitless when I can't check the thickness of the electrical cabling anyway.  But thanks for the suggestion. It would have made sense if it could all be checked.

 

Replacing the old Jabsco with the new version is going to end up an expensive and risky experiment because there are too many unknowns (other than 3 of the specs being higher than my current set up). I don't think it's worth the risk of damaging my electrics or calorifier. Both money and my energy/stamina¬†are factors I have to take into account. I'm not the nimble Clanger I once was ūüėÉūüėČ

 

I think I just need¬†a like-for-like replacement for the original water pump. Jabsco haven't replied to my enquiry about what that should be... yet. I'm concerned that I'm¬†going to end up with a rubbish quality one from another brand¬†that dies again in 3 years time or is going to result in a load of faffing with cutting new pipes or building a new box surround if it's a different size to the current one. I was hoping to do the job once, do it well, rebuild my boat and not have to think about it again. I could really have done without having no running water and such a major repair job...¬†in winter ... while not very well... and during the Great Plague ūüôÉ

 

[Insert Edvard Munch-like scream here]

 

And.... relax. 

 

Time to start again.

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FWIW the supply cable looks to em like twin 28/00.30, 2sq mm CCSA. I cant see it being any thinner and working long term like it has. If I am correct and assuming the pump  is at the front of the boat I would go with the one needing a 10 amp fuse even it it does  reduce the flow rate from the taps/shower.

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1 hour ago, BlueStringPudding said:

 The wiring is all built in behind walls and built-in furniture, and inaccessible. 

...

I've already pulled to pieces the kitchen to access the water pump and can't put that back together until it's resolved. To do the same to the back cabin (the only other living space) while I'm trying to live aboard, just to try and see a knob on the calorifier seems a bit fruitless

 

This was built as a hire boat? Did Black Prince really build the hire boats for their own fleet to be so unmaintainable? I would have thought they wanted ready access to everything just by undoing a few screws, so that if anything went wrong while the boat was on hire it could be quickly rectified.

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23 minutes ago, Tony Brooks said:

FWIW the supply cable looks to em like twin 28/00.30, 2sq mm CCSA. I cant see it being any thinner and working long term like it has. If I am correct and assuming the pump  is at the front of the boat I would go with the one needing a 10 amp fuse even it it does  reduce the flow rate from the taps/shower.

Thanks. The trouble is I can't find one with a 10A fuse that has more than half my current rate of flow. 7lpm is useless for a 65ft boat with multiple outlets (3 √ó sinks, 1 √ó shower, 1 √ó toilet, 1 √ó header tank automatic valve). My broken Jabsco is 14.4lpm with a 10A fuse and it's adequate but not speedy. I can't half that flow of water and have a useable bathroom.

All of Midland Swindler's pumps are rated at 20A or so, with 20-40 psi. Both too high for what I've got now.

Jabsco pumps are mainly 15A now. But I'm still working my way through their website. There's a 10A pump but it's got a much higher psi than my set up. So that's no good either. I can't seem to find a 10A fuse with a 20psi pressure.

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Par max 4 120 squids new on fleabay delivered. Fwiw when my par max 4 went tits up I replaced with parmax 1 at less money and it works perfectly, did the same on my last boat. 

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