Speed up black tank dump

[f6bits]

In my effort to clear out the black tank, I filled it up with water and then pulled the dump valve. Water rushed out at tremendous speed, then *really* slowed down.

Is this normal? To speed things up, I held the toilet flush down and this restored full-speed dump. I know the black tank vent works because when draining is slow, bubbles don't come back up the line.

[bartletts]

I thought the black tank had a plumbing vent on the roof? Mine seems to.

[JRTJH]

You said that the waste doesn't "bubble back through" when it slows down. That would be normal. Essentially, the black tank is a wide shallow pan with a 3" drain on one end and a "roof vent" on the other. When you first pull the dump valve, you'll get a rush of waste through the valve and into the sewer line. Then things will slow down to a slow flow for several minutes. When you turn on the black tank flush, it will continue this trickle as it washes out the remaining solid waste. Once the effluent is relatively clear, you're pretty much done and can close the dump valve and be on your way.

Some people (me included) close the dump valve, use the black tank flush to partially fill the black tank, then dump again to get a stronger flow to remove any additional solid waste. Some think this is "overkill" some "live by it" and some are "indifferent" I think that part is pretty much a personal opinion.

As for why the flow increased when you held the flush pedal on your toilet? I can only surmise that maybe the tank was pretty much empty and by flushing the toilet, you increased flow INTO the black tank which increased the flow you observed slightly.

Once again, it is pretty much normal for the black tank to "trickle flow" for several minutes after it is pretty much empty. Is that what you observed?

I can't imagine that your roof vent is clogged (at least not in the tank) but you might want to check from the roof side. The vent cover should be removable and with a flash light on a cloudy day or in the late evening, you should be able to see the "bottom" Another way to check is to put a water hose in the roof vent and listen in the bathroom for water flow. Or you could open the dump valve and watch for increased flow. Again, I don't think the roof vent is clogged, but it is possible.

[Halibutman214]

If you are in fact drawing a vacuum when dumping the tank you have a serious problem with your vent. When I dump it gushes out right down until the end. I would try it by filling the tank and have someone cycle the toilet flush while dumping. If it speeds up/slows down you have a clogged vent.

[Ruffus]

Sounds like you have something in your vent, maybe a dead squirrel or such! You might look at the vent cap, I found one of mine was actually hitting the top of the vent pipe because the factory had cut the vent pipe to long.:wave:

[chuck&gail]

Just one point. If on roof be sure you are aware that bees and especially mud daubers, might be building in the vent. Don't get stung, and don't get up and run off the roof!!!!

If in doubt, spray some wasp killer in there FIRST.

[f6bits]

What JRTJH describes is what I'm seeing. But I'll give the roof vent a look. I just didn't want to pop it open since the holding screw is sealed.

[golfpro]

don't worry about the thing being sealed, you can always reseal it

[JRTJH]

Sdayman,

Rather than take the roof vent cover off. if you can find a thin walled hose (sort of like a windshield washer hose and somehow connect it to a garden hose, I think a winterizing air to city water inlet "blow out" adapter would work) you could snake it into one of the sewer vent openings and get water down the black tank vent that way. If you hear water flowing into the tank, your vent is open and working. If the water backs up and overflows onto the roof. then you do have a clogged vent. Dirt dobbers have a way of liking those spaces, but they usually don't completely clog the vent stack. Good luck and let us know what you find... :)

John

[f6bits]

On my final dump this morning, I let it go on its own. There wasn’t as much of a slowdown this time, so it didn’t completely fill up my clear elbow like last time.

Again, there is no bubbling back from the sewer, so I know the vent is working. I just hadn’t seen it slow down that much before. It’s possible that some toilet “debris” got caught in the 90° elbow at the ground connection that slowed things down.

[SAD]

On my final dump this morning, I let it go on its own...

I stopped reading right thar... LOLz... :rofl:

[2011 keystone]

LOL LOL:rofl::rofl:

[f6bits]

I stopped reading right thar... LOLz... :rofl:

Don’t you want to know how it ended?

[SAD]

Don’t you want to know how it ended?

With a big whoosh?

[Zeb]

...love the potty jokes!

[johnnyrose]

Too Funny! Being the new guy it is good to see that the people in this forum have a similar sense of humor. Potty jokes will always be funny!