Black Tank Flush Leaked!

mraplx · 03-09-2015, 07:59 AM

We were on our second trip this weekend, and when I flushed the black tank the check valve leaked a fair amount of water. I would estimate I ran the flush for 5 minutes or so. Once I noticed the water dripping from the base of the outside wall I shut it off. I dried the inside out and continue to run fans on the interior. My question to the forum is, what to do about the underside? I have an appointment for service this Saturday for an unrelated matter, so I will bring it to their attention then. There is a black wrap on the underside that I think needs to be opened up at the edges. I poked a couple of small holes in the wrap and got no water. Without knowing how much water leaked it's hard to know if there is lots of water or just a little.

ninjahbob · 03-09-2015, 01:34 PM

Is it the waste valve that is leaking? If it is under warranty let the warranty people do the work if not I would open the underneath some to let it air dry and inspect for damage.
Post a picture if you can and you should get a lot of help.

**norty1** · 03-09-2015, 01:39 PM

When I flush and disconnect the inlet hose, any water between there and the check valve will drain out of the water input. That is not black water the way you described it.

I had a loose clamp on another rig that allowed some clean water to leak in the storage compartment. A turn of the screw clamp fixed it.

David472 · 03-09-2015, 01:47 PM

I think you're referring to the Black Tank Flush. There is a check valve in that line between the outside wall and the plumbing down to the black tank. The purpose of the valve is to prevent anything siphoning back into your external water supply from the Black Tank. Mine leaked the first time I used it. Now whenever I use it, I place a small bucket under the check valve (its in a closet with ours). It has never leaked after the first time, but I don't take chances. My understanding of how it works, if there is any reverse water flow or pressure (going toward your supply line) it dumps that water out the side of the valve. Although it's designed to do that, I'd rather catch any stuff in a small bucket.

mraplx · 03-10-2015, 06:44 PM

I have done all I can do to dry things out, I am worried about interior wall and floor, but the Jayco dealer can deal with it on Saturday.

Tharrison · 04-19-2015, 07:16 PM

Just experienced the same thing on our first trip. How was it resolved for you?

Higgy · 04-19-2015, 07:32 PM

Happened to me too when i just bought the trailer. Luckily my wife was inside and screamed. Not too much inside but i got the dealership to check it for dampness. Also kept heat in it to make sure it dried out well. If its still under warranty get them to look at it and also the wood cabinets to make sure they have not been damaged.
The check valve is there to protect the city water from contamination in case it siphons back from the black tank. (would take a lot of different scenarios to happen for it to do it) The check valve in this circumstance would draw air back into the hose line instead of sucking water from the black tank. Sometimes they can stick or break and result is the disaster we have experienced.

mraplx · 04-19-2015, 08:32 PM

The part was replaced by the dealer and the trailer checked for water in the surrounding area. According to the dealer there was no residual water, and all is well. I dried up everything I could and ran fans on the interior for 1 week after the incident. I used the trailer for the last week while working, and there is no sign of moisture or odor, so I think things are all good. Very frustrating, I have considered just bypassing this check valve in the future given its tendency to fail.

Fatfenders · 04-30-2015, 11:26 AM

Not sure if where your leak is, but you may want to read this:

http://www.jaycoowners.com/forums/f7...ood-26776.html

I had a major water leak when using the black tank flush port.

mraplx · 05-03-2015, 07:45 AM

That is exactly the part that leaked.

314BHDS · 05-03-2015, 08:06 PM

It's weird,I would think that the black tank flush is its own seperate line to flush the tank.I could see check valve on that line so nothing could come back to hose but don't see how it could get to city water

Higgy · 05-05-2015, 08:41 PM

You have to connect the hose from the black tank flush connection to the city water hosebib otherwise you wouldn't get any water to flush the tank. The check valve is on this pipework so that water will not have the possibility of being drawn back through the hose from the black tank if for some reason the city water main got shut down while you were connected to it and you had left the hose on and connected.

314BHDS · 05-05-2015, 08:51 PM

Man I feel like a dummy.I read into to much and was thinking the water in the trailer itself,not realizing it could back up into the supply from campground....

arkhillbilly · 05-12-2015, 04:39 PM

It could possibly happen, but the black tank is not pressured and the inlet hose inclines from underneath the unit to part ways up the side. The valve mfg states that the valve will vent water at any time. There are rubber flappers inside, and they will stick, causing the water to run out the top. They have a redesigned valve, that mounts on out side of unit, and sent me one no charge when mine sealed shut. and flooded my t/t. Had a long battle with Jayco and valve mfg. last year over this problem.

mcdillio · 07-09-2019, 06:37 AM

Few years late to this thread, but had a similar problem the first time I went to flush the black water on my 2019... ran it for less than a minute and had water dripping from behind the exterior wall. Since it sounded like the same issue the OP had, I looked under the bathroom sink and found the check valve. See pic; not a bad valve but pretty crappy quality control on Jayco's part. That is on my half bath. Flush didn't seem to be doing much for my full bath either, so I went searching for a problem there and found the pex line going to that tank is kinked and no water is getting through.

jbagnall · 07-09-2019, 07:12 AM

We've used our new camper three times so far. I'm religious about emptying the black tank, but haven't flushed it out yet. How often should we be doing that? After each time we dump it out?

But now, I'm afraid to after reading all of this! Hah.

mcdillio · 07-09-2019, 09:05 AM

Quote:

Originally Posted by jbagnall

We've used our new camper three times so far. I'm religious about emptying the black tank, but haven't flushed it out yet. How often should we be doing that? After each time we dump it out?

But now, I'm afraid to after reading all of this! Hah.

I'm new to this as well, but the guy that did our walk-thru at the dealer said every 2-3 times you dump it, and that seems to be the general recommendation.

Just know where your check valve is and make sure it's not leaking when you start flushing your tank.

Ours was starting to get stinky but because of the cut in my pipe I can't use the flush-out right now, so when I was emptying it the last time I went inside and just flushed the toilet for an extended period of time while dumping the tank. Also, I use a macerator pump which has a port on it that allows me to blast water back up the dump pipe into the bw tank. Once the tank is empty, I'll shut the pump off, blast water in there for 5-10 seconds, then turn the pump back on. I did that several times and was pretty impressed by how much additional brown stuff got pumped out.

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