I have a 1987 c& c my II. The original belt driven water pump has passed away. I’m not interested in rebuilding it. So I purchased n on demand pump. If there is anybody out there who has a simple diagram of how to install the new pum…thus eliminating he accumulator. I have a water manifold on this boat. There are 2 separate tanks managed the water manifold. I have a photo of the current set up I will attach here. The new demand pump only has of Cours and end in an out. I just can’t figure out when I look at the original plumbing where they need to know what are of this thing any help is appreciated. Thank you.
Changing out OEM water pressure pump to on demand pump need help..
- Thread starter Jimongee
- Start date
Wiring is the same as an auto bilge pump.
However, why would you replace one of the best pumps ever designed for boats with something inferior? Ours on Skipping Stone was over 30 years old. They are extremely easy to repair with just a few parts needed on hand to keep them operating well. Parts or pumps are available on EBay at a reasonable price.
However, why would you replace one of the best pumps ever designed for boats with something inferior? Ours on Skipping Stone was over 30 years old. They are extremely easy to repair with just a few parts needed on hand to keep them operating well. Parts or pumps are available on EBay at a reasonable price.
I always like a good puzzle and your photos and write up certainly don't make things any easier.
This, I suspect is the flow for your existing pump, maybe. Can you trace the unknown line which enters the pump suction and identify ? The pump suction and discharge are shown so just match these to the new to the new pump suction and discharge ports.
As for the accumulator, just discard the accumulator and connect line 1 to line 2 if you really want to get rid of the accumulator. It will make your system even smoother if you leave it in.
Anyways, it's your boat and the new pump will definitely smooth out the flow.
If it were me working on this, I would tidy up the tubing as I go and would remove ALL cheap vinyl mesh reinforced vinyl hose in your potable water system. Replace with the 1/2" nylon hose and all Qest fittings which were likely the original fittings. The vinyl hose will likely split at some time.
BTW, what does this mean :
This, I suspect is the flow for your existing pump, maybe. Can you trace the unknown line which enters the pump suction and identify ? The pump suction and discharge are shown so just match these to the new to the new pump suction and discharge ports.
As for the accumulator, just discard the accumulator and connect line 1 to line 2 if you really want to get rid of the accumulator. It will make your system even smoother if you leave it in.
Anyways, it's your boat and the new pump will definitely smooth out the flow.
If it were me working on this, I would tidy up the tubing as I go and would remove ALL cheap vinyl mesh reinforced vinyl hose in your potable water system. Replace with the 1/2" nylon hose and all Qest fittings which were likely the original fittings. The vinyl hose will likely split at some time.
BTW, what does this mean :
And I may as well ask what this means as well :
Last edited:
So thank you, Ralph Johnson. Regarding those two paragraphs it look like what the heck am I trying to say I have no clue something garbled up after I sent it. I certainly wouldn’t send that kind of nonsense. Makes no sense to me either. But thank you very much. I will do exactly what you talked about and clean the whole thing up and I guess I’ll take the accumulator out of the picture. My rationale there is that all three of my other Sailboat had demand pumps they worked like 1 million bucks as well as my multiple RVs over all these years. Same pumps no accumulator ran well so yeah I’ll upgrade to that and I’ll keep the other pump around just in case somebody needs it. Thanks very much.
Oh and one more thing, Ralph, regarding that unknown line on the suction side- I don’t have a clue. It leads back toward the stern under the sole. And I will have to Disconnect it and run some air thru it and see if I can figure out where the other end terminates. It has me confused too because this boat does have a starboard and a port water tank under the settee’s. But there are clearly two lines coming out of the bottom of that manifold so I would assume one is for one tank and one is for the other so again I can’t explain that line you’re asking a question about yet. After thinking about it if you have any ideas, I’m all ears. Thank you so much for your help.
Ralph’s photos and diagrams are excellent! I really like the labels and notes.
If it were me, I would try to remove line 2 completely, along with the accumulator…and take the loose end of line 1, and connect it to hose Barb where line 2 was connected…
Does the accumulator still work? If so, no need to remove it.
And I had a mystery loop in my fresh water supply (I also had 2 tanks). I could not figure out what that loop was for, so when I pulled one of the tanks, I also took that loop put of the plumbin.
Good luck,
Greg
If it were me, I would try to remove line 2 completely, along with the accumulator…and take the loose end of line 1, and connect it to hose Barb where line 2 was connected…
Does the accumulator still work? If so, no need to remove it.
And I had a mystery loop in my fresh water supply (I also had 2 tanks). I could not figure out what that loop was for, so when I pulled one of the tanks, I also took that loop put of the plumbin.
Good luck,
Greg
@Ralph Johnstone to the rescue.
Sure enough the Vancouver Wizard simplified the problem.
Me. I would say...When you are removing a pump. It has an Inni and an Outie. Place the Inni on the new pumps Inni and the Outie on the new pumps Outie. Power it up and your all done.
I like the accumulator. When they work they provide a more even water pressure between pump action. If they are broken. Then they are "easy" to replace. If they function I leave well enough alone. You can often pump up the accumulator to provide pressure on one side of the system. Water can not be compressed.. Air is another story. Compressed it relieves itself gradually like an old man...pushing water out of the accumulator.
What ever you do it is all ok.
Sure enough the Vancouver Wizard simplified the problem.
Me. I would say...When you are removing a pump. It has an Inni and an Outie. Place the Inni on the new pumps Inni and the Outie on the new pumps Outie. Power it up and your all done.
I like the accumulator. When they work they provide a more even water pressure between pump action. If they are broken. Then they are "easy" to replace. If they function I leave well enough alone. You can often pump up the accumulator to provide pressure on one side of the system. Water can not be compressed.. Air is another story. Compressed it relieves itself gradually like an old man...pushing water out of the accumulator.
What ever you do it is all ok.
And that's where you're quite wrong !
Inni and Outie refers to navels, or as you would say "belly buttons."
And quite wrong, once again !
An old man with air (gas) relieves himself with great gusto accompanied by loud, disgusting, flatulent sounds.
I don't know if that will tell you much as I would think the far end is somehow sealed off otherwise it would be spewing water every time you filled your water tank to the top.
Given some of the incoherent and rambling sentences put forward in your post #1, I believe if you follow this mystery line which is connected to your pump inlet, you will find an old keg of rum attached to it, slowly feeding into your potable water system. The original intention of the rum feed was to keep the crew in line but somehow I think you drank more than your fair share of the adulterated water and the rest is history. Sounds interesting anyways.
thanks…and once more…about my previous ’incoherent and rambling sentences’…I also read those with dismay. I was using talk-to-text because my darn screen protector was causing jumbled keystrokes. So I never saw those meaningless sentences until the other replies came in. Regardless I still get the ‘dumb’ award for not catching that glitch…sorry….
I'm with @capta on this; I'd fix the belt driven pump and keep the accumulator. I have that setup and prefer it to an on-demand pump. (Rebuilt the pump at year 23.) If the accumulator is full when we turn in, bathroom hand washing at night isn't enough to empty it and trigger the pump, hence it's quiet.
But I think you can think of the pumps and accumulator as independent things. If you remove the accumulator, just seal the hose connected to it. (I don't see a need to replace it.). If you remove the old pump, just put the new one in its place with the in and out connected the same.