View Full Version : Black Tank Dump Valve is Sticking

11-12-2012, 05:01 PM
A few days ago I dumped the tank it was pretty cold outside (37 F) well above freezing and the black tank valve was hard to pull. Today, it was about 39 F and the valve was VERY HARD to pull open. What do you experts suggest? Thanks in advance.

Viva Las Vegas JDR
11-12-2012, 06:19 PM
If a dump valve is defective, it's a pretty easy job to replace it.

However the cause of the problem should be determined to avoid a recurrence in the future.

Do you flush your black tank thoroughly when dumping, using a transparent elbow to ensure all waste material is out of the tank? Do you leave the black valve open when parked? Have you ever washed out the black tank with hot water to ensure there is no build up of solid matter at the bottom? Do you think the valve is frozen to the gasket>

When replacing your valve, spray the gasket with silicone, and once a year, disassemble the valve to apply more silicone spray.

To solve your current situation, try applying heat using a hair dryer to the valve to see if it comes loose. If not, try running some hot water into the black tank.

Please let us know how you make out.

The Newell
11-13-2012, 04:05 PM
Sometimes just lubing the shaft externally helps, but if you find yourself doing that almost every time you use it, it is probably time to replace it. Not too big a job, so replacing is just as easy as disassembling to lube the inside.

11-15-2012, 02:17 PM
This valve always sticks if not heavily greased both inside and out. I have replaced my guts on all 3 and found plenty of gunk and paddle pieces which all contribute to particles running up the paddle shaft and greasing solves this