Carver Owners Forum

Midnightsun wrote:Qr Bbpost Cycling on/off when not in use can only happen if the pressure drops as in a leak or the unit sensor is defective or the check valve has a small leak. It is not the larger output that caused this.

If he got a pump with a higher pressure than what he had, it sure can and will show up problems in the system that may have been lurking there before.....not suggesting by any means that you cant install higher volume and pressure pumps, just be aware there might be some unforeseen consequences, which can probably be overcome....

Was considering a greater gpm and pressure pump, then considered the cost difference and how much we use the on board water system and the fact the entire boat runs off the system and the possible issues mentioned here and decided if I had to replace the pump to stay with what we have. The other issue to consider is what is the supply gpm?

So I purchased a SeaFlo fresh water pump with the same specs as the ShurFlo. Also installed a Watts valve on the out flow side so if any future problems the system doesn't drain out. Got to say new unit is so quiet have to turn everything off on he boat to here it run. Haven't checked out the old ShurFlo pump out yet, but did notice the inlet filter screen was plugged up with a lot of crap. Most likely was my low flow issue? Found the same unit in 115v and purchased it pumping out bilge water if needed!

Got around to investigating the older ShurFlo fresh water pump. Cleaned the inline filter screen, hooked up a 12volt supply and low and behold it pumped like a champ. I got a spare or a good pump for another project.

If you're replacing the pump, you might consider a small pressure tank if one doesn't exist already - these will stop unnecessary cycling of the pump for small tasks like hand washing or wine glass rinsing.

On a similar note, I am surprised how disposable water pumps are these days - it seems as if for most no rebuild kits are available and no effort to support parts is made by the majority of manufacturers. Not to be a negative Nelly but It is a sad commentary for the state of things overall.

I looked at the repair kit for the ShurFlo pump, which by the way it appeared a previous owner may have replaced the pump part, but the cost of the repair kit for the ShurFlo pump verses an entire replacement SeaFlow pump was like $20-$30 if I remember right, so replacing the whole pump was the way to go I/M/O. And like I said the 20+ year newer models make hardly any noise when running.

Hi Gang,

Just wanted to join onto this thread if possible. Like some of us, we are experiencing consistent issues with our Shurflo 2088-423-344 water pump cycling on/off. It’s an original unit. It’s pumping just about every 5-10 minutes when not in use. Pressure seems acceptable but since the boat is still new to us, we aren’t sure what IS normal! All typical leak culprits have been inspected as best as possible. We don’t have a dock water connection. Hot water tank and everything forward of engine compartment is definitely not the issue.

I’m willing to remove the water pump and ultimately replace it hoping that that can rule out a potentially important cause. (And reduce noise!)

However…….I’m really not certain of the best access to remove the pump. It seems daunting. We have a 1998 355 Aft. Perhaps there is access from the aft cabin that I’m not aware of?? Or is another plan of attack more reasonable and easier on our bodies?

Any help is greatly appreciated!

Stay Safe, Greg

HI Greg, if you haven't been able to find a leak, it could be the pump itself. It could be leaking back through the internal check valve. Sometimes this repair can be as simple as dismantling and a good cleaning of the pump's internal parts. Considering its age though and the noise you mentioned, replacement is a good idea. If you install a new one though and the same thing happens, you have a leak that you haven't been able to find. It doesn't take that much of a leak for the pump to cycle every 10 minutes.

From what I recall, the pump is located under the salon entrance stairs in the engine compartment. Not the easiest thing to get to but doable from between the engines kneeling on the battery compartment covers.

Curious; I think yours would be the first 355 I've heard of with no dockside water inlet. Are you sure?

Greg, if your pump cycles once every 10 minutes it could be the pump, but as viper mentioned its not likely. a small drip at the water heater relief valve, transom shower, icemaker, any faucet or dockside water inlet will make the pump run every few minutes.
If its the pump itself, normally it will not shut off at all, or only for a few seconds.

I also have a 355. The pump is only accessible from the salon between the engines and to the rear of the boat. Not ideal for servicing.

Are any of them ideal for servicing. I had to replace the pump on my 3007 shortly after I bought it. Not a fun job but I did get it done.