Hello fellow Sailors, My wife and I just purchased a Hunter 34. The previous owner helped us recommision after the winter lay up. We have found that our port freshwater tank has a leak. Without removing the port setee, I've found all the fittings to be leak-free and secure. We still have a small leak, and the tank is suspect. The sole seems to to wet along the edge where the setee is attached to the floor. Since we had a period of little or no rain and it is still wet (not just damp) we have began to suspect the tank. The boat is located about 30 miles from a good hardware store, so before I begin the drive this weekend I'd like to know if there are any good products for sealing a small leak in the poly tank. I suspect that I will end up replacing the entire tank, but if I can use something to temporize the problem that would be great too. Thanks in advance for your replies. Mike
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Where's the leak?
Depending on the location of the crack and how much stress the weight of the water is likely to put on it to push it apart again, it MAY be possible to repair using heat welding. That's the only thing that has a prayer of working, 'cuz nothing will bond permanently to poly. I'll wait to explain to how to do it till after you tell me where the leak is.
Depending on the location of the crack and how much stress the weight of the water is likely to put on it to push it apart again, it MAY be possible to repair using heat welding. That's the only thing that has a prayer of working, 'cuz nothing will bond permanently to poly. I'll wait to explain to how to do it till after you tell me where the leak is.
Tank
Peggie, I just got your book today. Read it cover to cover. Excellent treatise! I had no clue that you were from Arkansas.
I'll be going to the boat in the morning, post some news in tomorrow afternoon. Thanks, Mike
Peggie, I just got your book today. Read it cover to cover. Excellent treatise! I had no clue that you were from Arkansas.
I'll be going to the boat in the morning, post some news in tomorrow afternoon. Thanks, Mike
Michael, if it is the tank, I might still have
the one I took out of my H34. I'd have to dig around the basement of my folks' house. You can have it for the freight. I'll get out there in a day or two.
the one I took out of my H34. I'd have to dig around the basement of my folks' house. You can have it for the freight. I'll get out there in a day or two.
Found the Leak
Fred and Peggie and Forumites, Thanks for you prompt responses. I was able to spend the day with our boat and located the leak. It is not the tank, but I suspect it might as well be. It located on the 1/2" suction fitting. It is the nut that is integral to the tank. Of course, it was on the side not visible from inspection and it was after I had removed the tank that I was able to locate the source. The crack in the nut is about half way around on the lower side of the tank. I would surmise that the nut/attachment to the tank froze over the winter and that is the reason for the leak. I was able to isolate that tank, so we still have a fresh water supply. Any suggestions on how to repair this? Is it repairable? Should I send Fred postage for his old tank? Again, any help would be appreciated. I really enjoy this forum. Thanks, Mike Hunter 34 "Slip Sliding"
Fred and Peggie and Forumites, Thanks for you prompt responses. I was able to spend the day with our boat and located the leak. It is not the tank, but I suspect it might as well be. It located on the 1/2" suction fitting. It is the nut that is integral to the tank. Of course, it was on the side not visible from inspection and it was after I had removed the tank that I was able to locate the source. The crack in the nut is about half way around on the lower side of the tank. I would surmise that the nut/attachment to the tank froze over the winter and that is the reason for the leak. I was able to isolate that tank, so we still have a fresh water supply. Any suggestions on how to repair this? Is it repairable? Should I send Fred postage for his old tank? Again, any help would be appreciated. I really enjoy this forum. Thanks, Mike Hunter 34 "Slip Sliding"
Peggy, I have a leak along the top seam....
On the port tank (H34) where the tank wall meets the top of the tank. It's about a six inch slit in the seam. Can it be repaired? (Mike, Sorry to break in on your thread)
On the port tank (H34) where the tank wall meets the top of the tank. It's about a six inch slit in the seam. Can it be repaired? (Mike, Sorry to break in on your thread)
Replies to both of you...
Mike, it's more likely that overtightening the thread-barb hose fitting cracked your tank than freeze damage...winterizing wouldn't protect it anyway. Repairing it is easy and inexpensive, but not without taking the tank out to take it to any plastics mfr who does spinwelding. They'd just knock the fitting out and spinweld a new one in for a cost of no more than about $10. But that cannot be done in place...the tank has to come out. Be grateful it's a water tank...'cuz NO one will work on a used holding tank. About tank fittings: threaded female fittings in tanks are NPT ("national pipe thread") standard, which are very slightly tapered...so slightly that in a fitting as short as a tank fitting, it's not visually apparent. But it is enough that overtightening the male thread-barb fitting can put enough stress on the female "collar" to crack it...not necessarily immediately, but sooner or later. The longest I've seen it take is 18 months. So fittings in plastic tanks should only be tightened just one full turn beyond hand-tight, plus only enough more to aim an elbow in the direction it needs to go, even if half the threads are still showing. Use no sealant...wrap the threads of the male fitting with Teflon tape. Never use a metal fitting in a plastic tank...plastic and metal have widely different thermal coefficients (technical term for "they expand and contract at different speeds and in different amounts")...it'll leak in hot weather, can crack the female tank fitting in cold weather. This applies to ALL plastic tanks. Joe, your tank will also have to come out and be heat welded. If it were a smaller crack, you might be able to heat weld it yourself, but 6" is a long one...to get a weld that's strong enough hold requires a pro...'cuz the weight of the water is gonna put a lot of pressure against a crack that long. Heat welding isn't as simple as just melting new poly into the crack...just the right amount of the tank wall--not too much, not too little--must also be melted at the same time to turn it and the new material into a single mass that "becomes one again" with the tank walls. Unless you're experienced at heat welding it'll be hard to get a weld strong enough to hold that isn't likely to weaken the tank wall. IMO, you're prob'ly better off just replacing the tank...'cuz better quality tanks have walls that are 50% thicker and are twice as thick at all the corners and wall "intersections" as the tank walls to prevent just what's happened to yours.
Mike, it's more likely that overtightening the thread-barb hose fitting cracked your tank than freeze damage...winterizing wouldn't protect it anyway. Repairing it is easy and inexpensive, but not without taking the tank out to take it to any plastics mfr who does spinwelding. They'd just knock the fitting out and spinweld a new one in for a cost of no more than about $10. But that cannot be done in place...the tank has to come out. Be grateful it's a water tank...'cuz NO one will work on a used holding tank. About tank fittings: threaded female fittings in tanks are NPT ("national pipe thread") standard, which are very slightly tapered...so slightly that in a fitting as short as a tank fitting, it's not visually apparent. But it is enough that overtightening the male thread-barb fitting can put enough stress on the female "collar" to crack it...not necessarily immediately, but sooner or later. The longest I've seen it take is 18 months. So fittings in plastic tanks should only be tightened just one full turn beyond hand-tight, plus only enough more to aim an elbow in the direction it needs to go, even if half the threads are still showing. Use no sealant...wrap the threads of the male fitting with Teflon tape. Never use a metal fitting in a plastic tank...plastic and metal have widely different thermal coefficients (technical term for "they expand and contract at different speeds and in different amounts")...it'll leak in hot weather, can crack the female tank fitting in cold weather. This applies to ALL plastic tanks. Joe, your tank will also have to come out and be heat welded. If it were a smaller crack, you might be able to heat weld it yourself, but 6" is a long one...to get a weld that's strong enough hold requires a pro...'cuz the weight of the water is gonna put a lot of pressure against a crack that long. Heat welding isn't as simple as just melting new poly into the crack...just the right amount of the tank wall--not too much, not too little--must also be melted at the same time to turn it and the new material into a single mass that "becomes one again" with the tank walls. Unless you're experienced at heat welding it'll be hard to get a weld strong enough to hold that isn't likely to weaken the tank wall. IMO, you're prob'ly better off just replacing the tank...'cuz better quality tanks have walls that are 50% thicker and are twice as thick at all the corners and wall "intersections" as the tank walls to prevent just what's happened to yours.
Just for info
If either of you guys need my old tank (Michael gets first pick) as I recall that tank is seamless and heat welded. It was original equipment in '86. I'll check as soon as it quits raining. (I have outside work to do.) I'm a fair weather worker too.
If either of you guys need my old tank (Michael gets first pick) as I recall that tank is seamless and heat welded. It was original equipment in '86. I'll check as soon as it quits raining. (I have outside work to do.) I'm a fair weather worker too.
Michael, it quit raining.
I just got home and have the tank. It's like new. On my web site is an email link. I'm standing by,,,,
I just got home and have the tank. It's like new. On my web site is an email link. I'm standing by,,,,
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