Mainship dockside water connection

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Derek

Senior Member
Joined
Nov 5, 2016
Messages
142
Location
Usa
Vessel Name
Donna Mae
Vessel Make
2005 Mainship 430
Tried to connect a hose to the dockside water connection . Completely stuck. Anyone ever find a source for the internal check valve, etc or complete replacement? Thanks!
 
Ive replaced them but never tried to take apart & repair. Id replace and consider messing with to see if it can be freed up. Could be hard water... try some CLR to soak?
 
Do you have a pic? I had to replace mine a couple years ago with a newer Jabsco model that required cutting a bigger hole, but came out fine and works well.
 
IMG_0729.jpg
 



Ok. I took a long Philips head and placed on the check valve and gave it a tap. Got it to move back a bit and felt the check valve spring push back. Now have a trickle of water. Gonna leave the hose pressure on it for a bit and hope it works itself loose.
 
Derek, that looks like the same one I replaced. Required a little cutting as the replacement was larger even though they are both Jabsco, go figure. I could not find a direct replacement but the part is pretty inexpensive. Might be worth replacing and getting it over with. Eventually it will fail again and could cause flooding of your boat if unattended. Below is an example. Several similar models available in white or chrome. Make sure you get the right connection to your boat plumbing.

https://www.amazon.com/Jabsco-Regul...t=&hvlocphy=9003386&hvtargid=pla-570026745320
 
Derek, that looks like the same one I replaced. Required a little cutting as the replacement was larger even though they are both Jabsco, go figure. I could not find a direct replacement but the part is pretty inexpensive. Might be worth replacing and getting it over with. Eventually it will fail again and could cause flooding of your boat if unattended. Below is an example. Several similar models available in white or chrome. Make sure you get the right connection to your boat plumbing.

https://www.amazon.com/Jabsco-Regul...t=&hvlocphy=9003386&hvtargid=pla-570026745320



Thanks Blue!
 
I wouldn’t try to fix the one in the boat, just replace it. You don’t want it to mess up and flood the boat.
 
I wouldn’t try to fix the one in the boat, just replace it. You don’t want it to mess up and flood the boat.

Agreed, especially for a $40 part. On my boat, the plastic casing on the fixture inside the boat had cracked and was leaking water just from the water pump, not even connected to shore. I only found it because my water pump was cycling at anchor every few minutes.
 
When we bought our new to us boat it had a dockside connection. Every single person I spoke with said to get rid of it. That included multiple surveyors, professional boat captains, and multiple owners. The downside is flooding your boat. The upside is the minor inconvenience of periodically filling your tanks. When we fill we use a hose dedicated to that function. It’s drained and the male and female ends screwed together . We put a in-line filter on that hose. No risk of growth or contamination. Of course we check that filter before and after filling the water tank(s). We also have seagulls inside the boat. I have no interest in having a water line with pressure in it open while I’m off the boat or asleep that’s connected to a inexhaustible amount of water. We had ours disconnected and glassed over.
 
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Well…. Now there is a small leak out the back making the fresh water pump kick on every 10 minutes. Ran to lowes and bought a pvc male threaded plug and screwed it in. All good. Gonna leave it for now as we are in week one of getting this boat fixed up. Always a longer list than planned and makes me wonder about how surveyors can miss so much [emoji35]. Both sea strainers leaking, front toilet doesn’t flush, both sump pumps not working. One step at a time.
 
Hippo. Someone as concientious as you should not worry about flooding your boat. Nobody should ever leave a hose connected when off the boat. If it were to flood when asleep, I can't imagine you wouldn't wake up from the sound of all your bilge pumps working. I'm in tune to every small sound when asleep on the boat. Anything unusual will wake me up. Curious why you'd remove it vs. just not connect to it. Also, I wonder how much the fear of flooding is real vs. myth. Pressure is regulated to 45 psi. If I disconnected the line inside the bilge, would the boat sink or would the pumps keep up? I also wonder how many boaters would never connect to city water but leave their boat unattended or sleep with the airconditioning running. Isn't that also an endless water supply being pumped into your boat?

This was discussed in a previous thread, but again, when at a marina, I love having a water connection. It provides a silent endless supply of clean water at constant pressue with your water pump turned off. To me anyway, it's not at all about filling tanks, but just a better overall water supply experience on board. Granted, my system is not as extensive as others, but still.
 
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Flood Prevention

When I lived aboard I put a volumetric control at the faucet. I think it was Melnor and measured gallons, not time. I’d just give it a twist from time to time and worried less about an onboard leak flooding the boat.

Melnor still sells the device, but last time I tried one it only worked with large flow rates - like a lawn sprinkler. I wanted it for drip hose and settled for their timer model. I suspect they are built more cheaply and are too inefficient to meter lower flows.

There’s probably a different brand that would work but I’m not aware of one.
 
I gotta tell you all. The PO left some rotten water in the tanks. Foamy and stinky. I have run 600 gallons of fresh through the system and can now at least shower. Gallon jugs and a brita filter for meals and brushing teeth. It amazes me how some people treated their boats. With all respect to the true boaters that are doctors out there, this is the second boat I have bought from a doctor and will never again do so….
 
I’m a doc. Think worst are prior owners who ran small businesses.LOL. But really think it’s the luck of the draw. In my circle of cruisers many are docs. As anal boat owners as you could imagine.
 
I don't recommend connecting to dock water. Many marinas prohibit direct connection. I had a connected water system leak problem that could have sunk my boat years ago. A few extra bilge pumps over the years is far cheaper than a flooded engine room or worse and better peace of mind. If the tank leaks its only water that is already on the boat. I use a Zero Water filter/pitcher for drinking water and coffee or tea, Better than Britta. Water from the Britta is still over 200 ppm. Zero water is 5ppm.
 
I gotta tell you all. The PO left some rotten water in the tanks. Foamy and stinky. I have run 600 gallons of fresh through the system and can now at least shower. Gallon jugs and a brita filter for meals and brushing teeth. It amazes me how some people treated their boats. With all respect to the true boaters that are doctors out there, this is the second boat I have bought from a doctor and will never again do so….

We don't use shorewater for two reasons:

1) If something fails in the pressure water system, I don't have the bilge pump capacity to keep up with the volume of water that would come in from a city water line.

2) The water in the tanks turns very quickly. Filling the water tanks periodically ensures the water stays fresh in the tanks.

To fix the issue use about 4oz of bleach for every 10 gallons of water. Then fill both tanks, then run the water through the cold taps. If you have a water heater bypass, engage the bypass and run the water through the hot and cold taps at all of the sinks and faucets.

DO NOT let bleach sit in the water heater.

Then empty the tanks. When I flush I fill the tanks once completely, then several times about 1/2 full until I can't smell bleach anymore.
 
Those ShurFlo water pressure regulators are so common for boats and RV's that I think if they were highly prone to failure where they'd allow unlimited flow-in and flood the boats, they'd be sued to like crazy and either change the design or stop selling them. They do fail of course -- I can buy one here for about $60 and they don't last forever -- but in my experience when they fail they usually stop the flow to a trickle, or entirely. Oddly and coincidentally, four boaters on our dock had to replace them this summer, but then all four boats were late 90's. When we bought our 1996 boat in 2015, that was one of the first replacements I had to make. I remember we were coming up the Hudson and fortunately Shady Harbor Marina had a spare in their marine store. I did have to clean the screen last summer -- it was full of bits and gross stuff. Didn't make me very confident about the city water purity, but then it could have been junk in my own shore water hoses too.

The pressure regulator aside though, like some others I'm a fanatic about not leaving an open shore water line connected to the boat while we're gone, or even away from the boat for dinner. Hoses can fail, hose clamps can fail. I'm pretty sure my three bilge pumps could keep up but I don't want to test that theory. It's not hard to be cautious. I put a garden hose valve on the quick-connect so when we leave even for a long dinner I'll just close the ball valve. And when we leave at the end of the weekend I always disconnect the hose entirely because I don't trust visitors or dock neighbors or kids to not touch our supply valve on the dock.

And then one other thing while we're talking water supply and (some) Mainships. I have a cruiser model, not trawler style, but I had a water problem I had a very hard time figuring out so I'll mention it here in case this is ever helpful to anybody. For a while our boat developed a significant list to port and I couldn't figure out why. Our fuel tank is midships, so that shouldn't have done it. After a while I noticed water dribbling out the water tank vent cap on the port aft quarter of the boat. I finally read the schematics and realized there was a check valve between the house water line and the 100 gallon water tank under the master berth on the port side. That check valve had failed so every time we connected shore water, it would fill that port water tank to the top and then push water up the vent line and run out the vent cap. So the port tank had over 800 lbs. of water in it, while the starboard water tank was almost empty, hence the list and the water running out of the vent cap. Anyway, so many things can go wrong with the water supply system on a boat I never leave shore water on or connected when the boat is unattended.
 
We don't use shorewater for two reasons:

1) If something fails in the pressure water system, I don't have the bilge pump capacity to keep up with the volume of water that would come in from a city water line.

2) The water in the tanks turns very quickly. Filling the water tanks periodically ensures the water stays fresh in the tanks.

To fix the issue use about 4oz of bleach for every 10 gallons of water. Then fill both tanks, then run the water through the cold taps. If you have a water heater bypass, engage the bypass and run the water through the hot and cold taps at all of the sinks and faucets.

DO NOT let bleach sit in the water heater.

Then empty the tanks. When I flush I fill the tanks once completely, then several times about 1/2 full until I can't smell bleach anymore.

Exactly. We had a water line blow off in our motorhome due to high pressure I guess, maybe just a bad connection. If that had happened in the boat it could have sunk the boat. And by using the water in the tank it stays fresher.
 
But the boat inlet (and I assume motorhome) should be regulated to a lower pressure, it's not a direct shore pressure inside your boat. I have to agree with KTH above, that....
1) The pressure is regulated to ~ 40 psi so not the same as just putting a hose into your bilge.
2) Even if the hose on the boat side of the regulator failed completely, I don't know that my bilge pumps cannot keep up.
3) If this was a common, or even occasional occurence of boats sinking this way, they would have been done away with or at least your insurance would prohibit them. It's probably an irrational fear and low risk with some common sense such as not leaving water connected when you leave your boat.

I'll add a couple more thoughts, some that I stated before. Your boat is full of holes below the waterline. For instance, if your raw water inlet hose to your main engine(s) became disconnected, the volume of water would likely be greater that you can pump through the city water inlet. Also, how many people leave their boat, even for extended periods sometimes, with the AC pump running? Is that not also pumping an unlimited water supply into your boat? If you are really worried, you could put a volume restricting meter on the hose that will shut it down, but again the risk is low especially with reasonable precautions.
 
Those ShurFlo water pressure regulators are so common for boats and RV's that I think if they were highly prone to failure where they'd allow unlimited flow-in and flood the boats, they'd be sued to like crazy and either change the design or stop selling them.

I'm not talking about the Shurflo water pressure regulators. I'm talking about any other fitting along the path of yards of water line and connector fittings.

I buy used boats and the boat lives in a region with seasonal hard freezes. I can't guarantee that somewhere in the system hasn't gone through a minor freeze.

I once owned a boat that the older compression fittings kept failing. Upon inspection I had fond that all of the them showed stress cracking from an improper winterization at some point in the past. After you've dumped your water tank into your bilge 6 or 7 times, you learn to distrust that system.
 
Bob is right. I had a lot of water in my bilge a couple weeks ago and didn't know why, so of course I started searching for the source. Turned out one of my prop shaft stuffing boxes was dribbling water pretty steadily (yet another item for the to-do list) but when I first started looking it occurred to me that I have at least seven below-the-waterline intakes or thru hulls. I can easily or quickly access some of them, but others would take significant effort. And that's not counting the eleven above-the-waterline thru hulls or tank vent-line penetrations. Eighteen holes or openings in the hull, about half below the waterline, it's a miracle the boat is still floating after all these years.
 
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