Black tank flush inlet port on Nautilus P4 - how to replace?

ajg617

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Darned if I can figure out how this is even kept in place. Went to flush the black tank before dropping it at the factory and water sprayed everywhere inside and outside. I can't see how this is even attached or if it is even two pieces, let alone get the old one out and find a replacement? It's almost like it broke in two given the gap in the outside washer.

black tank inlet outside.jpgblack tank inlet inside.jpg
 
Could you be lucky enough that the hose washer fell out, so it’s no longer sealing?

Nope. Unfortunately, per GD the whole panel has to be replaced. It's an older style where the clips in the back are part of the panel and not the inlet fitting. The replacement parts are new design and held in by a c-clip which won't fit in the older model I have. GD parts and B&B confirmed - need to replace the whole panel.
 
Nope. Unfortunately, per GD the whole panel has to be replaced. It's an older style where the clips in the back are part of the panel and not the inlet fitting. The replacement parts are new design and held in by a c-clip which won't fit in the older model I have. GD parts and B&B confirmed - need to replace the whole panel.

Well that’s not good. I just did this below, based on what some others had posted in other threads. Maybe you could just do away with that existing connection.


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Darned if I can figure out how this is even kept in place. Went to flush the black tank before dropping it at the factory and water sprayed everywhere inside and outside. I can't see how this is even attached or if it is even two pieces, let alone get the old one out and find a replacement? It's almost like it broke in two given the gap in the outside washer.

View attachment 50625View attachment 50626

I would remove & replace just that fitting...even if you have to cut it off with a Dremel tool. Use a brass water inlet fitting for longevity. Then install a female NPT to PEX fitting on the inside. Whatever style water inlet you replace it with make sure you remove the check valve feature... you don't want two check valves in the flush line. The other check valve is at the high point in the flush line, usually located behind your shower near the faucet and accessible through an access panel.

RV City Water Fill Inlet Flange Check Valve Water Hookup Connector 3/4 NH Female to 1/2 NPT Male Mount Lead-Free Brass Flush RV Water Backflow Preventer with Dust Plug for RV Camper Motorhome https://a.co/d/gAHdawa
 
'I think i would try something like this instead of replacing the whole nautilus panel.
https://www.amazon.com/Thetford-942...zuN5Tk4kufK0SuIPJhilA5e2m5OU9jMUaAu4JEALw_wcB

Maybe the old fitting will pop out of the holding clips on the panel with a little persuasion ? Then if possible pop the retaining clips out of the nautilus panel and install the new fitting with small screws ?

I had to replace my fresh water supply spigot while on a trip and that is exactly what I did. Pop off the "C" clip, remove the old spigot, drill small pilot holes for the new screw mount spigot and install. Word of caution, look behind the Nautilus panel before you drill pilot holes to make sure you don't drill into a water line. I had drilled the first of three holes before checking and almost drilled a waster line.
 
Well I don't think I'd do that. I'm sure you can fit something there without buying a new panel. Unless they are offering a free replacement?

That's what I understood when I picked the RV up - they all saw the broken fitting and said that should have been caught during their pressure test so they didn't pressure test the black flush.
 
'I think i would try something like this instead of replacing the whole nautilus panel.
https://www.amazon.com/Thetford-942...zuN5Tk4kufK0SuIPJhilA5e2m5OU9jMUaAu4JEALw_wcB

Maybe the old fitting will pop out of the holding clips on the panel with a little persuasion ? Then if possible pop the retaining clips out of the nautilus panel and install the new fitting with small screws ?

That's my backup plan and as [MENTION=27414]IBEW Sparky[/MENTION] noted, it would probably be a longer lasting and replaceable item. But, I'm still going to lobby for the replacement P4 since I've had to replace the blue valve last year - at least I'll have spare parts then. $275 for the replacement panel complete.
 
That's what I understood when I picked the RV up - they all saw the broken fitting and said that should have been caught during their pressure test so they didn't pressure test the black flush.

There is actually no way to pressure test the black flush line... it's not a closed system. It's just a line with a spray nozzle on the opposite end and a check valve in the middle.
Also your RV is a 2022... I would think those parts would be covered under the factory warranty.
 
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There is actually no way to pressure test the black flush line... it's not a closed system. It's just a line with a spray nozzle on the opposite end and a check valve in the middle.

Yeah I get it but all they had to do is connect a hose to it and turn the water on and someone would have gotten a shower and my water alarm would have gone off - did for me and had a mess behind the wall to clean up.
 
Yeah I get it but all they had to do is connect a hose to it and turn the water on and someone would have gotten a shower and my water alarm would have gone off - did for me and had a mess behind the wall to clean up.

Did you unscrewed the female fitting off of the backside of the flush port yourself? How tight was it and where is it leaking from? Any cracks in the fittings? Just trying to figure out why it would start leaking all of a sudden.
 
Did you unscrewed the female fitting off of the backside of the flush port yourself? How tight was it and where is it leaking from? Any cracks in the fittings? Just trying to figure out why it would start leaking all of a sudden.

Fitting was fine. So was the washer. The inlet must have cracked. I noticed it was very loose when I went to flush before dropping off at Elkhart because I knew they were going to change bathroom gate valve. Minute I turned water on I got wet. I notice my fresh inlet is also loose but so far not leaking. I didn't hook water up the entire outbound trip until Elkhart. It was ok when I left just not when I got there. So yes I was behind the wall. First thing I checked was if pex fitting was secure and it was. The reason I knew it was ok before I left was due to April snow I had to de-winterize just a couple days before and I added about 5 gallons to the black tank through that port.
 
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I am slightly afraid of using the flimsy feeling ports on the N panel. I ended up putting brass elbows with shutoffs on both the fresh water port and the black water flush port. Now I just hook the hose onto the brass elbows. Feels more secure and easier to work with. Cheap solution.
 
Just a quick follow-up - there are replacement ports from https://www.rvlocksandmore.com/Replacement-Tank-Flush-Connection-No-Valve - parts supplier for B&B Molders. My part number was BBT-032-0004 which is hard to find on their website. The difficulty is getting the old one out. The second tech I spoke with told me to use a hacksaw blade to cut the old port in four pieces. Once you do that, you can fold a couple of the pieces in and the old one will pull out. The replacement then just snaps in.
 
New Nautilus panel came in the mail today. But, I'm going to try the unofficial repair on the old one first. Was surprised that they also sent a new black tank flush valve and spray nozzle which looked nothing like I thought it would.
 
New Nautilus panel came in the mail today. But, I'm going to try the unofficial repair on the old one first. Was surprised that they also sent a new black tank flush valve and spray nozzle which looked nothing like I thought it would.

They are good that way. When they messed up a valve while doing a "courtesy water system pressure test" that I didn't ask for they sent me a whole new panel with everything on it except for the two switches and pump LED light.
Can you post a picture of the black tank spray nozzle... curious to see what it actually looks like.
 
They are good that way. When they messed up a valve while doing a "courtesy water system pressure test" that I didn't ask for they sent me a whole new panel with everything on it except for the two switches and pump LED light.
Can you post a picture of the black tank spray nozzle... curious to see what it actually looks like.

I'm not exactly sure how this stays in place in the tank. The lower end is female thread presumably to the check valve assembly.

spray nozzle.jpg
 
I'm not exactly sure how this stays in place in the tank. The lower end is female thread presumably to the check valve assembly.

View attachment 50969

Thanks for the picture. Not sure how they would attach that inside the tank. The black tank check valve isn't located at the tank itself. It's located higher up in the RV to allow water to flow back down to the tank and also back down to the hose fitting. In my RV it's located behind the shower near the faucet and is accessible by removing an access panel in the linen closet.

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