Blackwater hose sealing

[Tkeeth]

Hi, just seeing if anyone has some advice on sealing a blackwater hose. I have a steel tank, in it's way out. Until I can get a new plastic one made, trying to stretch this one. I had to remove the hose from the tank a few weeks ago to replace the macerator impellar. The nipple on the tank has some corrosion and is preventing it from resealing. I have sanded as best i can and trmmed the hose back, double clamped as tight as I can yet it still wants to leak. Does anyone suggest a sealer that will help seal this off?

[tkeithlu]

OK, you're trying to jury rig this until you can replace the tank, so creative responses that are not exactly the professional way of doing things are allowed. Let me give you a procedural clue that seems to escape some mechanics, often on automotive engines. Get a good quality sealant, such as DuPont 5200. Coat the outside of the nipple, not the inside of the hose, and ease it into place, leaving the clamps loose. Do not tighten the clamps until the sealant has set. Then tighten the clamps. People tend to put on the goo and tighten the clamps immediately. That prevents to goo from making a pressure seal, because it just oozes out wherever the clamp tightens. You end up with just the strength of the hardened goo for your seal, when what you need is to create a hard rubbery gasket and then, and only then, tighten down on it with the clamp. Good luck with it. If you don't have access to 5200 or comparable, buy the silicone sealant with the largest number of years of claimed life - that's a measure of how little water it has in it, and as a result, how little it will shrink when dry.

[Tkeeth]

Thats just the type of idea i was looking for. I will try that! Thanks!!

[hellosailor]

Personally I think 3M 5200, 0r 4200, would do the job. A heavy wrapping on the nipple with wide thick teflon tape (it comes in multiple grades, the yellow for gas lines is probably around) followed by a little soap or lube to force a heated (moe flexible) hose over it, should also do. Then I'd apply a couple of steel zip-ties (if available) with a proper git-em-tight tool, or the nylon ones with a gorilla pulling with pliers. Sewage being such a nice concept, I'd probably still also overwrap that with either silicone tape or butyl tape (both are self-amalgamating) and then place a couple of conventional hose clamps over THAT. That puppy ain't ever gonna leak again. By the way, if you can find a real plumbing supply store, a big one, they sell all sorts of damage control clamps and materials. The self-amalgamating tapes are a good start, but if all else fails, some punctured bicycle tire tubes (free at any bike shop) make a good repair wrap.