Leak from my holding tank May 16, 2018, 11:16:42 pm So, it's clear where it's coming from. Mostly I'm wondering what I'm getting into here. Ya know, before I start unscrewing things.I haven't used this as a black tank, but this looks original so it's like 40 years old. The order of operations as I see it:Drain it, undo the fittings, hope that I can find something that'll work without having to re plumb. This is the outlet, so maybe that won't be such a chore...?
Re: Leak from my holding tank Reply #1 – May 16, 2018, 11:35:47 pm It looks like the threaded fitting has broken free of the tank. It was originally spun-welded into place.It needs to be welded back into place, using a hot air welder, after a good clean up.Some RV shops can weld this or possibly a local plastic fabrication shop. I have not had good, long-term success with adhesives, used on holding tanks.It could be too old to repair, the plastic may be brittle.New tanks are available in a variety of sizes, the required fittings can be spun-welded into place.Larry 1 Likes
Re: Leak from my holding tank Reply #2 – May 26, 2018, 05:55:59 pm Thanks! I figured out why I only had the one holding tank, the toilet was self contained, and fairly full. Haha. Oh boy.
Re: Leak from my holding tank Reply #3 – June 11, 2018, 09:18:29 am Quote from: technicolorwildlife - May 16, 2018, 11:16:42 pmSo, it's clear where it's coming from. Mostly I'm wondering what I'm getting into here. Ya know, before I start unscrewing things.I haven't used this as a black tank, but this looks original so it's like 40 years old. The order of operations as I see it:Drain it, undo the fittings, hope that I can find something that'll work without having to re plumb. This is the outlet, so maybe that won't be such a chore...?They have some incredible water tight tape these days that can even be used underwater. Could be worth trying before an expensive fix.
Re: Leak from my holding tank Reply #4 – June 11, 2018, 11:44:40 am Quote from: Sawyer - June 11, 2018, 09:18:29 amThey have some incredible water tight tape these days that can even be used underwater. Could be worth trying before an expensive fix.Cracks on holding tanks can be temporally repaired with Eternabond tape.Leaking fittings are next to impossible to fix without disassembly and re-glueing or replacement.None of the speciality epoxies I have tried have held well over any period of time. Hot air welding or spinning in a new fitting are the suggested ways to repair a leaking fitting.Larry
Re: Leak from my holding tank Reply #5 – June 11, 2018, 12:40:30 pm Quote from: Larry W - June 11, 2018, 11:44:40 amHot air welding or spinning in a new fitting are the suggested ways to repair a leaking fitting.Larry, I'm not familiar with either of those terms. Could you clarify what hot air welding and spinning are?
Re: Leak from my holding tank Reply #6 – June 11, 2018, 01:23:43 pm Quote from: HiLola - June 11, 2018, 12:40:30 pmLarry, I'm not familiar with either of those terms. Could you clarify what hot air welding and spinning are?I know that spin welding is just what it sounds like, you spin the fitting really fast, and the friction melts the two pieces together. 1 Likes
Re: Leak from my holding tank Reply #7 – June 11, 2018, 01:37:54 pm Quote from: HiLola - June 11, 2018, 12:40:30 pmLarry, I'm not familiar with either of those terms. Could you clarify what hot air welding and spinning are?Thermal plastics can be welded with very hot air, using plastic rods to fill gaps and cracks.Ridgeyard 1600W Hot Air/Hot Gas Plastic Welder Welding Gun with Speed...Spin welding was already explained.Larry 1 Likes As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: Leak from my holding tank Reply #8 – June 11, 2018, 01:54:52 pm Hi Greg. Hot air welding is like a hot glue gun on steroids. I worked in a semiconductor fab (back in the day) and on occasion got to weld polypropylene pieces of sheet together with a hot air welder. Not as fussy as welding metal, but still what I would consider an 'art'. You have to get it right the first time. We had a fancier welder, but I found this on ebay: 1500W Hot Air Torch Plastic Welding Gun Welder Pistol+ 4pcs Speed Nozzle... RonB
Re: Leak from my holding tank Reply #9 – June 11, 2018, 02:28:23 pm Thanks for the explanations. We didn't weld any plastic (thankfully) when I was in the nuclear submarine repair business.
Re: Leak from my holding tank Reply #10 – June 12, 2018, 12:31:42 pm Quote from: Larry W - June 11, 2018, 11:44:40 amCracks on holding tanks can be temporally repaired with Eternabond tape.Leaking fittings are next to impossible to fix without disassembly and re-glueing or replacement.None of the speciality epoxies I have tried have held well over any period of time. Hot air welding or spinning in a new fitting are the suggested ways to repair a leaking fitting.LarryHow about some of that new spray on stuff that's supposed to stop any leaks? Any experience with that? I'm always looking for a bailing wire way to fix things. Comes from being an old gyppo logger I guess. Spent my entire working life making temporary repairs that ended up lasting for years.
Re: Leak from my holding tank Reply #11 – June 12, 2018, 12:46:11 pm I don't know if this "as seen on TV" tape works as advertised, but it might be worth a try.#1 Waterproof Tape - Patch, Bond, Seal, Repair with Flex Tape
Re: Leak from my holding tank Reply #12 – June 12, 2018, 12:48:09 pm Quote from: Sawyer - June 12, 2018, 12:31:42 pmHow about some of that new spray on stuff that's supposed to stop any leaks? Any experience with that? I'm always looking for a bailing wire way to fix things. Comes from being an old gyppo logger I guess. Spent my entire working life making temporary repairs that ended up lasting for years.I guess anything is worth a try. The spray can sealers are not adhesives, they will not repair the crack, just seal it.Mechanical motion in the crack will probably cause the sealant to fail after a time.Larry