Black H2O Tank Flush leak

flymerc · 07-10-2018, 05:11 PM

First time draining the black water tank, I connected a water hose to the black water tank flush connector and water leaked inside the camper .

I found the black water flush connector broke.

Easy find, easy fix, I'll pick one up at Keystone RV.

**Sunline Fan** · 07-10-2018, 09:00 PM

It's interesting to see how one of these failed. Have to wonder why it did, but it could be many things. Black tank flush kits were pretty rare on Sunlines- they were basically special order only except on fifth wheels.

B&B molders is still in business today (and owned by Thetford), so the part is very common and available. It also can be used as a city water inlet, so it may be advertised as that, Sunline just used a different type of city water inlet. If Keystone RV can't help you out, here it is and pretty cheap: https://www.ebay.com/i/232124807743?chn=ps

In an effort to keep your supply hose sanitary (even if it isn't the drinking water one), I'd recommend sticking with the version that has a check valve.

**JohnB** · 07-12-2018, 09:22 PM

Quote:

Originally Posted by Sunline Fan

It's interesting to see how one of these failed. Have to wonder why it did, but it could be many things. Black tank flush kits were pretty rare on Sunlines- they were basically special order only except on fifth wheels.

B&B molders is still in business today (and owned by Thetford), so the part is very common and available. It also can be used as a city water inlet, so it may be advertised as that, Sunline just used a different type of city water inlet. If Keystone RV can't help you out, here it is and pretty cheap: https://www.ebay.com/i/232124807743?chn=ps

In an effort to keep your supply hose sanitary (even if it isn't the drinking water one), I'd recommend sticking with the version that has a check valve.

Hi Jon,

Actually B & B makes 2 types. One with the check and one without. Sunline would install the one without the check in the blank tank flusher.

I actually bought all the parts from Sunline when I had the T2499 to add a tank flusher. This is what they sent me.

The vacuum breaker

You can see the B & B molding water inlet and they did not have the check. You can also see the vacuum breaker that they sent. Sunline would pipe this up so the vacuum breaker was above the tank by a certain distance. I believe they want that non check valve water inlet so that once the flushing is done, and the user unscrews the hose from the water inlet, the lack of check valve allows that vacuum breaker to work correctly and the water will drain back out the side of the camper since there is no check valve in it. The Sunline method may not work right if you add a water inlet with a check in it.

Oddly enough, my 2004 T2475 has a Sunline tank sprayer installed in it. It was part of a custom order. And Kitty and Gary's T299SR parts camper had one too which is the first I saw installed in the walls.

Hope this helps

John

**JohnB** · 07-12-2018, 09:25 PM

PS, I still have those 2 B & B molding water inlets. I will see if I can find them tomorrow. They are "somewhere" in my pile of PEX stuff in the barn. I know the right crate to start looking in at least.

**Sunline Fan** · 07-12-2018, 09:33 PM

Quote:

Originally Posted by JohnB

Hi Jon,

Actually B & B makes 2 types. One with the check and one without. Sunline would install the one without the check in the blank tank flusher.

Good to know! I did see both types available. With the addition of the vacuum breaker, it makes sense why you'd need the one without the check valve!

flymerc · 07-13-2018, 05:12 AM

My 2004 Sunline Solaris has what appears to be a factory installed Black Water tank flush system.

It has this installed in lieu of a check valve.

Next time the Black Water tank requires dumping, I'll try out the "repaired" flush system.

Thank you all for your knowledge and assistance!!!!

**JohnB** · 07-14-2018, 05:41 PM

Yes, that is the vacuum breaker. Your floor plan seems to allow it being found in a cabinet with access. Great! Other floor plans have them buried in a wall which make maintenance access an issue if anything ever goes wrong with it. I do not recall anyone making a post on an issue with one, but since there are not that many installed by the factory that may be why. It is a simple valve and it may be very reliable.

Thanks for sharing the pic. A good learning opportunity.

John

flymerc · 07-17-2018, 05:06 AM

This morning I had the opportunity to use the "repaired" Black water flush system.

When I applied water through the newly replaced exterior flush fitting (without a check valve), there seemed to be no water flowing into the black water tank.

Looking at the way the system is plumbed, the vacuum breaker is in line between the exterior flush connector and the black water tank, and thus I suspect may not be functioning correctly.

Anyone know how the black water flush system works, and what may be the issue with the lack of water flowing from the flush connector to the black water tank?

I'm thinking I need to replace the vacuum breaker with a check valve and plumb it more in line instead of a tight 90 degree like the factory has it plumbed.

Or perhaps there is something I need to do to allow the vacuum breaker to release vacuum and allow water to flow?

Thank you in advance!
Shawn

shellynne24 · 07-17-2018, 07:19 AM

We have a sunline.T 2753 and the black water tank shows full all the time just wondering if getting to the float is tough or if anyone has had this problem and can it be fixed

flymerc · 07-17-2018, 09:59 AM

I believe the sensors in all three tanks are inductive sensors and not float sensors.

As the fluid fills in the tank the liquid grounds the sensor and thus completes a circuit that is displayed on the tank level panel.

I would think if the Full Light is displayed when the tank is not full, debris may be on the sensor.

To remove the debris from the sensor you will need a flush wand (https://www.amazon.com/Valterra-A01-.../dp/B000BGHYDO )that hooks to a garden hose and is inserted into the toilet (while flushing to open the ball valve into the black water tank) thus rinsing away the debris.

shellynne24 · 07-17-2018, 10:55 AM

Thank you I will give it a try when the wand gets here

**Sunline Fan** · 07-17-2018, 12:30 PM

Agreed, no floats involved.

I do like the wand a lot, and it keeps clean/new tanks nice. But for cleaning up old ones, the best suggestion I've heard is to fill the tank up half way or so with water, and dump a big bag of ice down the toilet. Then go drive around with it. The ice cubes will slosh around and break up the stuff stuck to the sides of the tank.

shellynne24 · 07-17-2018, 12:53 PM

That sounds like a great idea I did fill it about 1/3 and used the tank fresh with no luck I will try your idea thanks

flymerc · 07-17-2018, 04:04 PM

My water inlet fitting for the black water flush system, I installed has a check valve, which will not allow the black water flush to work

I can't seem to find any water connectors without the checkvalve.

Anyone know where to get an exterior water connector WITHOUT A CHECK VALVE????

Thanks in advance!

**JohnB** · 07-18-2018, 05:45 AM

Hi Shawn,

See if this helps. I tracked down the actual B & B molding who made these parts including the spray nozzle, the vac check and the water inlet connection that is suppose drain out the water.

See here for their web site Recreational Vehicle Products – B&B Molders

And here for a good write up on "The Flusher". A lot of good detail in there. Never knew this existed until your question.
http://www.bandbmolders.com/wp-conte...2-Install-.pdf

I found the inlet valve here marketed by JR Products which is a big aftermarket place selling all kinds of RV hardware etc.

I have bought from Eastern Marine before and had positive outcomes. Here the word description fits. https://www.easternmarine.com/water-...160-85-a-2pz-a

It seems Amazon has it too. I just do not like the wording description as they do not say anything about the check valve or not. If you zoom in you can see the B & B symbol at the top and the part number is what B & B calls out https://www.amazon.com/JR-Products-1.../dp/B000BGOCO8

On the J & R site it does state that part number 160-85-a-2pz-a "does not" have a check valve. Scroll to the bottom of the page
JR Products :: Catalog

If all else fails, I can dig through my pile of stuff and see if I can find one of the ones I bought from Sunline back in 2005/2006 time frame.

Hope this helps

John

flymerc · 07-18-2018, 09:52 AM

John,

As always, THANK YOU!!!!!!!!!!!!!!

You sir are a wealth of good detailed information!!!!!!!!!!!!

A true blessing!!!!!!!!!!

Thank you very much John, I greatly appreciate your help and knowledge!!!!

**JohnB** · 07-19-2018, 09:57 PM

Your welcome! Glad it helped.

We have a very diverse group of folks here from all backgrounds. It is truly a team effort. By folks talking/posting we all learn something from this. Someone on the forum can usually help on most anything or point you in the right direction to sort it out.

Let us know how the fix comes out.

Thanks

John

flymerc · 08-04-2018, 06:46 PM

Thanks to John, I got the correct flush water inlet.

Hooked everything up and no joy.

Made an adapter to apply water directly at the flush fitting on the black water tank. (to check for a plugged flush nozzle)

Sure enough that bugger is plugged up!😠

It looks like removing it to clean or replace it will be tons of fun...NOT!

That fun is awaiting for another day.

flymerc · 08-05-2018, 03:24 PM

After installing the correct exterior flush fitting ;(without a check valve) / (Thank you John for the link to the correct part!!!) the black water flush still does not work.

I removed the PEX inlet line at the flush fitting on the black water tank. I then installed a DIY adapter that I hooked up to a garden hose with minimum restiance. (thinking I could clear the obstruction from the flush nozzle with water pressure)

When I turned on the hose and opened the toilet ball valve it was painfully obvious that water pressure alone would not clear the debris clogging the flush nozzle.

The only option I have at this point is to remove the flush nozzle and mechanically clear the obstruction.

Here's the $10,000 question; does anyone know if the flush nozzle can be backed out of the adapter hole without removing the adapter? (the flush fitting has tefloyn tape on it's threads, indicating it is threaded into the tank adapter)

mainah · 08-05-2018, 06:24 PM

OK you need a backflow preventer to keep you from contaminating the fresh water system of whatever you are connected to that's what they are for they should let water into your tank but not back out even my black water drain connector has a one way valve it only lets water into the black tank. I don't think you can buy a one without a valve otherwise it would defeat the propose you sure it is installed the proper way around? The U shaped plumbing posted probably is a vacuum breaker it would be installed above the waterline of the tank the ideal of the breaker is to stop the receding flow of water from drawing stuff into the draining hose connection from the effect of water leaving the hose.