RV.Net Open Roads Forum: Tech Issues: Black Tank Dump Valve

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tech Issues

Open Roads Forum  >  Tech Issues

 > Black Tank Dump Valve

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 2  
Next
Sponsored By:
CarnationSailor

Carnation,WA

Senior Member

Joined: 12/21/2009

View Profile



Good Sam RV Club Member

Offline
Posted: 06/02/21 06:45pm Link  |  Quote  |  Print  |  Notify Moderator

When I dump a full black tank, the valve opens very easy, no problem. I flush the tank for 5 to 10 minutes, then I close the valve for 5 minutes to let it partially fill. When I then pull the handle to open the valve again, it is so difficult that I almost cannot open it. Been this way for a couple of years, and now I thought I might do something about it.

I put tank valve lubricant in the tank periodically, but that doesn't seem to make any difference. Any ideas why full it is a piece of cake to open, and after flushing and partially filling, you almost need a gorilla to open it.


2015 Crossroads Rushmore Springfield
2015 Chevy Silverado 2500HD Duramax


CA Traveler

The Western States

Senior Member

Joined: 01/03/2004

View Profile


Offline
Posted: 06/02/21 07:04pm Link  |  Quote  |  Print  |  Notify Moderator

Something in the seal dries out over time and then swells with usage? Regardless why not just replace the valve and be done with it?


2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland

Bob


LadyRVer

Florida

Senior Member

Joined: 09/04/2007

View Profile



Good Sam RV Club Member

Offline
Posted: 06/02/21 07:13pm Link  |  Quote  |  Print  |  Notify Moderator

Might try spraying handle/metal rod with silicone. Or probably just need to replace. I did my tank, took me about 3 hours.. but I got it done.

IAMICHABOD

Sunny So Cal

Senior Member

Joined: 12/12/2011

View Profile



Good Sam RV Club Member


Posted: 06/02/21 07:14pm Link  |  Quote  |  Print  |  Notify Moderator

I found that lubricating it during a dump as in this video works.

I have used this method for many years to lubricate my valves and have had no problems with them at all.

This Video will show how to do it


2006 TIOGA 26Q CHEVY 6.0 WORKHORSE VORTEC
Former El Monte RV Rental

Buying A Rental Class C


Durb

NW

Senior Member

Joined: 01/15/2016

View Profile



Good Sam RV Club Member


Posted: 06/02/21 08:46pm Link  |  Quote  |  Print  |  Notify Moderator

Do you turn off the water to the black tank rinse before opening the valve? Could be the incoming water is building pressure inside the tank and binding the valve.

Lynnmor

Red Lion

Senior Member

Joined: 07/16/2011

View Profile



Good Sam RV Club Member


Posted: 06/03/21 07:29am Link  |  Quote  |  Print  |  Notify Moderator

Durb wrote:

Do you turn off the water to the black tank rinse before opening the valve? Could be the incoming water is building pressure inside the tank and binding the valve.


Good thought. The tank has a vent thru the roof and can only build pressure if that vent is blocked. What can happen is that the vent pipe slipped down into the tank and is now under water, or even worse, resting on the bottom.





jdc1

Rescue, Ca

Senior Member

Joined: 05/30/2011

View Profile


Offline
Posted: 06/03/21 09:35am Link  |  Quote  |  Print  |  Notify Moderator

Add liquid detergent to the tank occasionally.

CarnationSailor

Carnation,WA

Senior Member

Joined: 12/21/2009

View Profile



Good Sam RV Club Member

Offline
Posted: 06/03/21 09:36am Link  |  Quote  |  Print  |  Notify Moderator

Durb wrote:

Do you turn off the water to the black tank rinse before opening the valve? Could be the incoming water is building pressure inside the tank and binding the valve.


I think if this was happening, the vent pipe would also have to be mostly blocked, but not so much that normal usage builds pressure. I could test this by waiting 30 minutes or so after partially filling tank to give it time to bleed off. If it works easily after giving it time to bleed off, then I think this might prove your theory.

CarnationSailor

Carnation,WA

Senior Member

Joined: 12/21/2009

View Profile



Good Sam RV Club Member

Offline
Posted: 06/03/21 09:40am Link  |  Quote  |  Print  |  Notify Moderator

Lynnmor wrote:

Durb wrote:

Do you turn off the water to the black tank rinse before opening the valve? Could be the incoming water is building pressure inside the tank and binding the valve.


Good thought. The tank has a vent thru the roof and can only build pressure if that vent is blocked. What can happen is that the vent pipe slipped down into the tank and is now under water, or even worse, resting on the bottom.


If I recall correctly, the roof top vent cap is attached to the vent pipe with screws. So it seems unlikely that the pipe slipped down; however, if it did, then the vent cap should be missing. At any rate, I'll check out this possibility.

CarnationSailor

Carnation,WA

Senior Member

Joined: 12/21/2009

View Profile



Good Sam RV Club Member

Offline
Posted: 06/03/21 09:51am Link  |  Quote  |  Print  |  Notify Moderator

IAMICHABOD wrote:

I found that lubricating it during a dump as in this video works.

I have used this method for many years to lubricate my valves and have had no problems with them at all.

This Video will show how to do it


Looks like a good solution for sure - if your dump valves are exposed and easy to get to. I would have to either drop the coroplast or cut a hole in it, and I'm not ready to go there yet.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 2  
Next

Open Roads Forum  >  Tech Issues

 > Black Tank Dump Valve
Search:   Advanced Search

Search only in Tech Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:




© 2021 CWI, Inc. © 2021 Good Sam Enterprises, LLC. All Rights Reserved.