Log In | Register
Skip to main content
Topic: Emptying my black and gray tanks (Read 409 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.
Emptying my black and gray tanks
When I go to empty my tanks and remove the cap, about 1-1.5 cups of liquid spills out.....no other issues with my tanks.....can anyone point me in the right direction? 

Thanks,

Bill
2013 31' Silver Twin Bed
Semi-retired 6/21....
Re: Emptying my black and gray tanks
Reply #1 –
Hi Bill;  It looks like one of your tanks has a leaking gate valve, and what leaks by gets contained by the seal on the outlet cap(s).  Does your 30' have a combined gray/black water dump at one location?
   The gate valves can leak if the four corner bolts are too loose. Also the gaskets can wear after quite a while of use and allow leakage.  You could try tightening the bolts just a little on the offending gate valve, to see if that helps.
  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Emptying my black and gray tanks
Reply #2 –
Quote from: pdl2win  - 
When I go to empty my tanks and remove the cap, about 1-1.5 cups of liquid spills out.....no other issues with my tanks.....can anyone point me in the right direction? 
Thanks,
Bill 

Probably just need to replace one (or both), dump valves.  Over time, the seals deteriorate and begin to leak.  Fairly simple job but MAKE SURE both grey and black tanks are empty before removing the valves!  Plenty of YouTube videos on "how to".
https://www.youtube.com/watch?v=d2OWEL5VQpE

This listing is for example only - I haven't ordered anything from these guys before.
Valterra RV Holding Tank Dump Valve with Plastic Handle 3 In.
Good luck!
Zia, our 2013  27’ RK
2001  Jeep  Wrangler
Land of Enchantment
Re: Emptying my black and gray tanks
Reply #3 –
Quote from: Jaxon  - 
Probably just need to replace one (or both), dump valves.  Over time, the seals deteriorate and begin to leak.  Fairly simple job but MAKE SURE both grey and black tanks are empty before removing the valves!  Plenty of YouTube videos on "how to".
https://www.youtube.com/watch?v=d2OWEL5VQpE

This listing is for example only - I haven't ordered anything from these guys before.
Valterra RV Holding Tank Dump Valve with Plastic Handle 3 In.
Good luck!

I'm in the middle of my annual "LarryW" enzyme deep clean........once I finish that take care of this...thanks for the help
2013 31' Silver Twin Bed
Semi-retired 6/21....
Re: Emptying my black and gray tanks
Reply #4 –
Quote from: RonB  - 
Hi Bill;  It looks like one of your tanks has a leaking gate valve, and what leaks by gets contained by the seal on the outlet cap(s).  Does your 30' have a combined gray/black water dump at one location?
   The gate valves can leak if the four corner bolts are too loose. Also the gaskets can wear after quite a while of use and allow leakage.  You could try tightening the bolts just a little on the offending gate valve, to see if that helps.
  RonB

Thanks Ron...yep the gray/black valves empty through the same exit point.....I'll tighten the bolts as you recommended!!
2013 31' Silver Twin Bed
Semi-retired 6/21....
Re: Emptying my black and gray tanks
Reply #5 –
Just a note Bill; If you tighten them too much it will be hard to get them open to dump, and possibly even harder to close them again, which could leave you in a real predicament. I've even had to loosen them for winter, so I would have an easier time getting the valves open and closed. (The bolts change length to shorter when cold and are harder to open/close, and the rubber seals are stiffer when cold, making it harder to slide open/closed).     RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Emptying my black and gray tanks
Reply #6 –
Quote from: RonB  - 
Just a note Bill; If you tighten them too much it will be hard to get them open to dump, and possibly even harder to close them again, which could leave you in a real predicament. I've even had to loosen them for winter, so I would have an easier time getting the valves open and closed. (The bolts change length to shorter when cold and are harder to open/close, and the rubber seals are stiffer when cold, making it harder to slide open/closed).     RonB

Thanks Ron.....I'll do just a bit of micro-adjusting and see if it does the trick.....
2013 31' Silver Twin Bed
Semi-retired 6/21....
Re: Emptying my black and gray tanks
Reply #7 –
I replaced mine a couple years ago.  First the plastic handle broke, then it was hard to close - lubing helped.  I got tired of wondering "what next"  and after a good clean-out, replaced them both.

"Why is hyphenated non-hyphenated, but non-hyphenated is hyphenated?"
Joel & Terry Wiley
dog Zeke
2013  31 IB   Orwan   / 2011 CRV Tow'd LWEROVE
Re: Emptying my black and gray tanks
Reply #8 –
If so inclined, the dump valves can be disassembled, cleaned and lubed with spray silicone, usually with success. The slot the blade pushes into can fill with debris, preventing a tight seal.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Emptying my black and gray tanks
Reply #9 –
Hi Larry; I didn't know that!  I did replace the seals once. I also put in stainless screws with nyloc nuts so that they would stay consistent. I spray with WD-40 up into the sliding valve, when I dump at home, and sometimes with the valves partly open to get some 'lube' up into the sliding places.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Emptying my black and gray tanks
Reply #10 –
I learned long ago from this group that to lube the slice valves is to drill a small hole near the top of the valve housing (see photo) just big enough to insert a spray can tube. Then spray either silicone or WD40 (but not lithium grease) in the housing while working the slice back & forth will help free up the valve. Then close the hole with a small stainless screw. Repeat when needed. 
2010 RB "Monty"  &  2021 RB "Villa Verde"
2004 Born Free 26'
1998 Beaver Patriot 33'
1992 Barth Breakaway 28'
1982 Fleetwood Jamboree 23'
1982 Dolphin/Toyota 22'
Re: Emptying my black and gray tanks
Reply #11 –
Quote from: Mike Coachman  - 
I learned long ago from this group that to lube the slice valves is to drill a small hole near the top of the valve housing (see photo) just big enough to insert a spray can tube. Then spray either silicone or WD40 (but not lithium grease) in the housing while working the slice back & forth will help free up the valve. Then close the hole with a small stainless screw. Repeat when needed. 
I may have to do this. I been having to lube mine up more often than I like.
Steve and Jill, Steve posting
1999 26.5 Mid-Bath