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Resolved!! Black water tank won't drain

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Jim
 Jim
(@j_a_wolfe)
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We've tried all we can figure out to drain the tank. Hubby pulled down the insurlation enough to check that the open/shut valve is working. We are at Disney, and don't want to take it to a repair place if we can avoid it. Any ideas on diagnosing and fixing?
Many thanks!

Put a hose down the toilet and ran water in, then did a flush from the external hose. It's empty now!! 🙂

 
Posted : October 8, 2017 8:03 AM
Jim
 Jim
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I have had this problem twice. First time I dropped the insulation and loosened the valve enough to push a wire up to the tank and that solved the problem until the next time. After the first time I purchased a cap for the sewer outlet that has a place to attach a water hose. Was able to to back feed water into the sewer outlet and black tank to free it up. I think something was left in the tank during assembly of the coach that can move over the outlet hole of the black tank. It just needs to be moved when that happens.

 
Posted : October 8, 2017 8:32 AM
Jim
 Jim
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Not a unique problem, seems the lazy assembler don't always get the cutout when installing the inlet pipe, so they just leave it in the tank to move around and block the outlet every now and then.

 
Posted : October 8, 2017 10:19 AM
Jim
 Jim
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Blockage can be a frequent problem if not enough water is used when flushing solids into the black tank. The solids buildup on the bottom of the tank and will block the outlet. We always count to 10 when holding the pedal down to flush solids.

 
Posted : October 8, 2017 12:55 PM
Jim
 Jim
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Blockage can be a frequent problem if not enough water is used when flushing solids into the black tank. The solids buildup on the bottom of the tank and will block the outlet. We always count to 10 when holding the pedal down to flush solids.

This is very true.
In our 39MB the pipe for both toilet's dump into the tank in the shallow end, and a corner. So yes, extra water is needed to move the waste to the deep end. I can only guess it is the same for most models.

Rick

 
Posted : October 8, 2017 3:40 PM
Jim
 Jim
(@j_a_wolfe)
Posts: 10846
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Blockage can be a frequent problem if not enough water is used when flushing solids into the black tank. The solids buildup on the bottom of the tank and will block the outlet. We always count to 10 when holding the pedal down to flush solids.

This is very true.
In our 39MB the pipe for both toilet's dump into the tank in the shallow end, and a corner. So yes, extra water is needed to move the waste to the deep end. I can only guess it is the same for most models.

Rick

I agree, solids can cause the problem and using sufficient water is a must. However in both cases that was not the problem. As I stated, with the first incident I pushed a small wire up the pipe into the tank and it immediately broke loose in full force. Something is in my tank that completely cover the hole during transit.

 
Posted : October 8, 2017 7:44 PM
Jim
 Jim
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I have heard stories about the PLUG that was drilled being left in the tanks.. that would/could cause a blockage like that.???

 
Posted : October 9, 2017 9:24 AM
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I have heard stories about the PLUG that was drilled being left in the tanks.. that would/could cause a blockage like that.???

Yes it could. I haven't had a problem with our Redwood but our previous RV had the plug left in the tank, it eventually did work it's way out but it killed our sewage pump when it jammed the macerator blades and burned out the motor.

 
Posted : October 9, 2017 3:24 PM
Jim
 Jim
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That is exactly what happened to our last rig. Got to the point that it helped contribute to the tank splitting. After removing the old tank tipped it up on end and sure enough clink clank clunk to big to fit through any holes. What a pain in the butt that was to deal with. My black water tank now the valve is very hard to pull. I dumped a large cup of used vegetable oil into the tank right after emptying it drove it a couple of hundred miles. Now it is working smooth as silk again even better than it ever has.

 
Posted : October 10, 2017 7:52 PM
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