Slow Drip from Black Tank???

boatdoc

Well-known member
After getting an occasional "different" smell in one area of the trailer I put it off as a dead varmint somewhere near the area. Well, that isn't the case. I got up yesterday morning to find the critter or whatever is was and found a very slight leak on a very hard to get to black tank outlet in the bowels of the 3670.
The drip, once every 82 seconds, is right at the exit port of the tank where the valve slides into it. It has a band clamp on it and I was able to tighten it just a smidgeon but with no success, still dripping. So I guess what I'm asking is, have any of you had the valves out of the outlet port and what if anything seals the two? How does a band clamp tighten up on an ABS fitting and an plastic tank.
I really can't do anything major now, but intend to fix this properly when back home at the shop where all the tools and a nice concrete floor are available.
Thanks
 

HappyKayakers

Well-known member
If you're talking about the blade valve, it has a seal on each side. I've changed mine and it was a real bear getting at it and then making sure the seals stayed put while positioning the valve body on the pipes. As I recall, I knew that one of the seals slipped when I had a slow leak at the valve body. :-(
If the valve has been in there for awhile, you'll probably need to order/buy new seals for the project.
 

JohnDar

Prolifically Gabby Member
It was some time ago, but I thought there was a member that posted an extensive report, complete with photos, of his valve replacement. I tried a search, but couldn't find it.
 

boatdoc

Well-known member
Not the valve itself, but the joint that the valve fits in which is molded in the tank. The tank is some kind of plastic and the valve nipple, which goes into the molded tank, is ABS. How do they seal these two pieces? Thanks
 

hoefler

Well-known member
If it is threaded, use Teflon tape. If it is smooth, most likely a solvent weld. If it is a solvent weld that is not sealing, you can try draining the tank and let it dry out for a day or two. After it has dried out, get some pipe cleaner. Apply the cleaner very liberally and make sure it wicks into the area of the leak. Next apply a very liberal coat of ABS glue. Let it dry and it should hold. Make sure you use Universal or ABS glue, not PVC or CPVC glue.
 

slmayor

Founding California Northern Chapter Leader
And here's the redneck fix. Billy May's Mighty Putty really works. We had a leak at a fitting on our spa and didn't want to take the whole thing apart. Ray used Mighty Putty and it's been holding for over two years. Marine epoxy might work too, as you well know, you can use it under water..LOL Good Luck and see you in Yreka!
 

SLJKansas

SLJKansas
Don't put off fixing it. I had to put mine in the shop for a black tank leak, they had to replace the tank. It started as a drip and ended up that the tank cracked around the flange area. Mine may have started like yours.
 

hoefler

Well-known member
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