We overfilled our forward water tank and it started leaking from the inspection port. The tank is in it's own compartment and there's was standing water with no way for it to drain. I had to use a sponge to get it out. Does anyone see an issue with drilling a hole in the bottom so it drains to the bilge if this happens again?
To drill or not to drill...
- Thread starter Project_Mayhem
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Assuming the hole will be drilled through a wood panel, no problem if you seal the sides of the hole with some epoxy.
And don't you mean, when it happens again?
Get yourself a water flow meter (Amazon link) and it will be less likely to happen in the future.
And don't you mean, when it happens again?
Get yourself a water flow meter (Amazon link) and it will be less likely to happen in the future.
The tank is in a fiberglass enclosure built under the forward berth. Tank level meters are in the works and the top will be resealed but in the meantime, it'd be nice to implement a temporary solution that only takes two minutes
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Isn't there a vent to the tank? There must be one. The vent tells you when you are close to filling the tank. Please explain how you can overfill a water tank. Or for that matter any properly vented tank, i.e., fuel, for example.
This is a job which is relatively easy to fix and yet the results (if left uncorrected) may quite likely destroy a good portion of the water tank supports. I don't see how you can live with something like this.
#1 job is to make the inspection port 100# sealable when closed. Even with a head of 1 -2 feet of water on top of it. If you don't do that, don't waste any further time on this problem.
Just a waste of time and the surrounding wood will eventually rot because you cannot get the drain hole down to floor level and the boat never sits exactly horizontal.
If that gets the most water out, do that EVERY time it overflows and hope for the best as far as rot goes.
Please read reply #5 over and over a few times and it will eventually hit you. The problem is that you're standing way too close to the problem and by now, you're eyes are probably exhausted.
While you're down there, send a few (more than one) pictures of the inspection port. Sounds like you've got the same setup as I do and I can't make mine leak even with a two foot head up to the overflow drain.
There is a vent. I think it vents through the stanchion but I haven't stuck my head in the hanging locker to confirm. The vent lines from the tanks go to a T and I believe they go upward so they are most likely venting to the stanchion. My holding tank vent was clogged so it's totally feasible that this one is too
. The fill plate always had water overflowing when we stuck a hose in it. I just assumed that the line was too small to handle the flow of water from the garden hose. Perhaps if the inspection port was sealed properly, overflow would come out of the vent instead? When the tank is full or close to being full, do you hear noise from the vent?
I will get some pics when I can. I don't know what the supports below the fiberglass liner look like. It's at the bow so it's probably just tabbing to the hull but there could be some exposed wood and we don't want that to rot. Keep in mind that you have a different brand of boat so the setup is probably different. My tank sits in a fiberglass liner
Yes, if the tank is watertight then the first place overflow will come from is the vent. The problem you’re having is that the tank is below the vent outlet so the water comes out the failed seal first. When filling the water tanks I usually just keep going until water comes out the vent. That might help clean it out a bit too. When filling the fuel tank I listen closely to the vent sound to tell when the tone changes as a sign the tank itself is full.
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Same issue on C310, if water level comes above the tank in filling tube the inspection cap starts leaking .
we have electronic water sensor which gives beep alarm when the 2 wires are under water. same sensor is also wired to several bilge points with a on / off switch for every wire set.
Just put 2 stanless screws in the top side of the tank and connect them to the alarm. you can fine tune it with the lenght of the 2 screws.
If you have a water meter on top of the tank maybe you can use two of the bolts of it when insulated from the tank meter.
we have electronic water sensor which gives beep alarm when the 2 wires are under water. same sensor is also wired to several bilge points with a on / off switch for every wire set.
Just put 2 stanless screws in the top side of the tank and connect them to the alarm. you can fine tune it with the lenght of the 2 screws.
If you have a water meter on top of the tank maybe you can use two of the bolts of it when insulated from the tank meter.
The tanks are plastic and when overfilled the shape of the tank distorts breaking the seal and allowing water to seep out through the inspection port. The solution is to not overfill the tank. Using a water flow meter can reduce the chances of over filling.
True for many, but perhaps not all.
I have a custom plastic water tank with all access points spin-welded in. No leaks. Since the other tank is the holding tank, that's an especially good thing. (!)
What's the point of an inspection port that's welded shut? I'd be curious to see if an expanding test plug or a couple of floor flanges sandwiched on either side of the plastic with a gasket would do a good job of sealing
No, I see water come up the vent, and stop filling. I don't have inspection ports on my tanks. Wouldn't your solution be to secure and seal those so they don't leak? That allows you to use the vent as the "filled" indicator like I do, re post #5.
i think FastOlson meant that the flange of his port was welded to the tank. One would assume that the opening part of the port would be removable, like a circular Beckson port.
I think it's safe to say that my vent is clogged and that the port on top of the tank needs to be sealed
If you can come up with those pics, I'm sure we can find a solution.
If it's the same inspection port as my potable water tank and holding tanks are (were) the only thing in the universe that will stick to poly, bend and flex without losing the adhesion is Permatex #2 :
The Hunter factory used 4200 or 5200 on the outer ring and it wasn't even in contact with the poly when the screws were removed.
Of course you'd be a complete fool to believe what I say on some far flung boating site so buy some (a few bucks) and smear a blob on the exterior of your poly tank and see what luck you have in trying to remove it after a day or so. Impossible. It never hardens. The only thing that removes Permatex #2 is any form of alcohol. Use Permatex to seal the outer ring to the tank, not the "O" ring under the cap.
As far as the large "O" ring in the port goes, let's see what shape it's in when you remove it.
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Interesting that my 93 MkII C30 does have a drain hole in front of the v-berth water tank. It's right in front of the shut off valve. It drains into the bilge by going beneath the tank pan and to the port side where the head water intake is. There is a limber hole in the inside corner of the head forward bulkhead where it goes towards the boat center.
It's to the left of and under the water strainer in this photo. The hatch over the water strainer is the one in the forward bulkhead of the head.
