Fresh water, pump pressure troubleshooting

rybad

Petty Officer 1st Class
Joined
May 20, 2004
Messages
215
I just acquired a 1987 Carver Mariner.. very nice boat. Only problem is there is almost no water pressure at any faucet. The water tanks appear to be holding pressure without leaks, but the water pump will never shut off either. Its a sureflo pump, about 17 years old, 2.9gpm with a 45PSI shutoff. If I turn it on, I get very little water from any faucet. Cant see any leaks anywhere, but again, the pump will run continuously.

I have checked the strainer and it is clear. Wondering what steps to take. I know I can get a new pump for about $90, but not sure if that will solve the problem as I've never working on water systems before.

Thanks for any input.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,582
Close off the hose leaving the pump/pressure switch and see if the pump turns off. It likely won't. Time for a new pump.
 

Grub54891

Admiral
Joined
Jun 17, 2012
Messages
6,142
Check the strainer to see if its plugged,on the input side of the systym. Sometimes the strainer is before the pump, and it can't get water to it as they do get plugged. Had one that the owner replaced the pump on once,still no pressuer,turned out his water heater had split a tube due to poor winterization. The pump would run,but the water would exit through the boats exhaust sysym,therefor no leaks inside the boat. I only found it as I was standing on the back deck and wondering why I could not find the leak. Then I spotted the slight water movement at the exhaust. Problem solved!
 

smokeonthewater

Fleet Admiral
Joined
Dec 3, 2009
Messages
9,838
My thought is this... the pump is way past it's expected life.... Order a new pump... this MAY not solve the problem but should be done anyhow.... THEN it's a very simple process... if the pump won't build pressure but it has good flow when the faucet is on then you have a leak... if it won't move any water at all then you either have an intake restriction or a BAD leak.....

I would suggest a new intake strainer for your new pump also..... cud in the valves causes poor problems.

Even if you got the current pump working it could likely die at any moment .... possibly right after you get lathered up in the shower.
 

PCUK

Petty Officer 3rd Class
Joined
Sep 22, 2011
Messages
82
It's almost certainly a worn out pump. As a first step, remove the pump and inspect it for wear. You can probably get a service kit but while it's out you may as well replace it.
 

PCUK

Petty Officer 3rd Class
Joined
Sep 22, 2011
Messages
82
It's almost certainly a worn out pump. As a first step, remove the pump and inspect it for wear. You can probably get a service kit but while it's out you may as well replace it entirely.
 

rybad

Petty Officer 1st Class
Joined
May 20, 2004
Messages
215
Thanks guys.. I already checked the strainer and its clear. I think I will just get a new pump.. but does anyone have any suggestions on what size.. I realize I should match what is there, but I want to make sure I have good water pressure, and I dont want to blow a hose of course.. but what do I look for GPM, or shut off pressure.. I guess Im not clear on what the shut off pressure means and if that effects the water pressure at all (I assume not) I'm thinking GPM is going to give me the pressure if anything.

Any suggestions, or should I just match the existing one to be safe?

Thanks again for all your input.
 

rybad

Petty Officer 1st Class
Joined
May 20, 2004
Messages
215
Thanks guys.. I already checked the strainer and its clear. I think I will just get a new pump.. but does anyone have any suggestions on what size.. I realize I should match what is there, but I want to make sure I have good water pressure, and I dont want to blow a hose of course.. but what do I look for GPM, or shut off pressure.. I guess Im not clear on what the shut off pressure means and if that effects the water pressure at all (I assume not) I'm thinking GPM is going to give me the pressure if anything.

Any suggestions, or should I just match the existing one to be safe?

Thanks again for all your input.
 

rybad

Petty Officer 1st Class
Joined
May 20, 2004
Messages
215
Thanks guys.. I already checked the strainer and its clear. I think I will just get a new pump.. but does anyone have any suggestions on what size.. I realize I should match what is there, but I want to make sure I have good water pressure, and I dont want to blow a hose of course.. but what do I look for GPM, or shut off pressure.. I guess Im not clear on what the shut off pressure means and if that effects the water pressure at all (I assume not) I'm thinking GPM is going to give me the pressure if anything.

Any suggestions, or should I just match the existing one to be safe?

Thanks again for all your input.
 
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