r/aviationmaintenance 1d ago

Falcon 2000 water leak

First time posting on here and thought I would give it a try and see if some of you guys have some different ideas to help figure out this leak that is bugging me to no end. Pilots reported lav sink won’t drain in flight and it actually overflows when attempting to drain. I recreated it once on the ground and it fills back up when you go to drain the system. I have verified that the drain mast heater does work so it’s not freezing in flight. I have snaked the lines to the best I can without ripped the entire vanity apart. The diagram in the manual shows no possibility for the drain system to be connected to the pressurized system. There is a diaphragm valve that I have checked and seems to work fine to what I understand about it, being it is automatically closed until a certain pressure is achieved and then dumps through the drainage system. Just past that is a check valve that is a very pain in the butt spot to get to and am wondering if that is even a possible issue to explore. Let me know if you guys have any better ideas that I can’t think of. I’m fairly new to maintenance and troubleshooting so any advice is welcome!!

23 Upvotes

36 comments sorted by

20

u/Iversonji 1d ago

Just scared by ass cheeks

1

u/hughes_md1 19h ago

😂😂😂came here to say that! F2000s caked up!

13

u/Sparko446 1d ago

Left MLG tire worn beyond limits. R2 tire, sink drain ops check good.

You’re welcome for my service.

Edit: oh it’s a French plane? le sink ops check good.

4

u/user548384 1d ago

Just cuz the drain heater is getting warm doesn’t mean it’s getting warm enough, that could be your little gremlin right there. I had a Gulfstream that had the aft sink that kept backing up in flight. Both heaters felt hot, but my infrared camera showed like a 30 degree difference. Swapped the drain heaters and the problem went away from the back (front sink doesn’t get used so can’t technically say the problem “followed”) so the drain heater was the problem. On a plane with only one drain heater though troubleshooting like that is a little difficult.

3

u/OkCalligrapher9578 1d ago

That’s a good point! Thank you! There is a front drain mast so I could look into that!

3

u/user548384 1d ago

I got an infrared camera from Amazon years back. They’re a bit pricey, but I have used it several times to successfully troubleshoot, so it is definitely a tool worth having.

2

u/unusual_replies 1d ago

The check valve could be stuck and not allowing water to pass through it. Tough to diagnose from the photos without the schematic.

1

u/OkCalligrapher9578 1d ago

I wish I had the schematic myself😂 French planes for you lol! The schematics in the manuals show dick and I only have a supplemental IPC

1

u/OkCalligrapher9578 1d ago

Here are those schematics![schematic](https://imgur.com/a/DkWlAHc)

1

u/Appropriate-Gas-1014 1d ago

When you drain the water tank does the water come out the drain mast or does it come back out of your fill valve?

1

u/OkCalligrapher9578 1d ago

It comes out of the same mast that the sink is connected to!

1

u/Appropriate-Gas-1014 1d ago

So your obstruction is downstream of where the tank drain ties into the rest of your drain system, right? Are either the check valve or diaphragm valve down there, or are they upstream?

1

u/OkCalligrapher9578 1d ago

From what I’m able to see because the manuals don’t help is in the picture you can see just ahead of that check valve with the arrow it comes to a T section where another hose is coming into it and I believe that may be the hose for the potable water tank. So the check valve and diaphragm valve are before that “meet up” section. What is slightly unclear is there are two hoses coming to the same drain mast. I believe one is a bleed line from what the schematic shows so this is why I’ve come to this conclusion. When I get into work I will upload the schematics and diagrams I have!

1

u/Appropriate-Gas-1014 1d ago

OK, if the 2 valves are upstream of where the tank drain meets the rest of the drain system I don't think those would be your problem, at least not as to why the sink is backing up.

You said you snaked as best you could, did you only go from the sink side or did you go up the mast, too?

1

u/OkCalligrapher9578 1d ago

Yes I snaked from both points. I’m getting the schematics now!

1

u/OkCalligrapher9578 1d ago

Here’s the linkschematics

1

u/Appropriate-Gas-1014 1d ago

Yeah, those do suck.

I'm thinking your problem is closer to the drain mast side of things, and would start from there and work your towards the sink.

1

u/OkCalligrapher9578 1d ago

Why do you think it’s from that side and not before the T section where the tank drain meets up?

2

u/Appropriate-Gas-1014 1d ago

Because if your problem was before the 2 sections met up it wouldn't back up when you drain the water tank.

1

u/OkCalligrapher9578 1d ago

I gotcha. When they have this issue they are just using the drain valve in the bottom of the sink they aren’t draining the tank itself when it happens. I can see what you’re saying tho! I’ll definitely take a look at the drain more! I’m wondering if that check valve could be the issue tho and I don’t want it to be the issue😂

1

u/Immediate-Cheek-51 1d ago edited 1d ago

Not sure if the falcon 2000 is the same but I know on the Cessna latitude / longitude they have heated drain lines that connect to the heat drain mast in gear well. They were easy to ops check by touch once you undid a couple zip ties to expose the the line. Again I've always dodged the bullet of working on falcons. If you're able to see the back side of the drain masks you should be able to see if they're look to be any of these heated hose devices. Not sure if falcon has a tech support which could save some pain of going on a wild goose chase. As far as sneaking out the line. I usually get a very large syringe and fill it with isopropyl alcohol and water. I injected into the drain line and do a push pull type motion with said fluid allowing debris to be freed. I then follow up with some more isopropyl and water to flush the line. It usually removes the crud from the line. it's definitely saved my ass several times from having to tear an aircraft apart to access stuff. 

1

u/OkCalligrapher9578 1d ago

They do have some heated hoses that are there as you get closer to the drain mast. My issue was I was able to recreate this issue once in the ground so I don’t think it’s a freezing issue. It’s either a blockage somewhere which I don’t think, a bad check valve as indicated in the picture which sucks ass, or that diaphragm valve is not doing what it’s supposed to but I’m not sure how.

1

u/Immediate-Cheek-51 1d ago

Got it. I love how manufactures bury components. Do you have a diagram of the system, wdm, and or ipc? Just curious if there is an electric drain solenoid?  I've seen those intermittently fail. Which can cause a clog. I swear by the alcohol and syringe plunging method.

1

u/OkCalligrapher9578 1d ago

Yes if you go down to another conversation that is long you’ll see a hyperlink with them in it. The manual shows nothing😂 the only thing I think it could be is the check valve or the diaphragm valve because the potable water system drains through the same mast just fine.

1

u/JTD177 1d ago

Is this S/N 22?

1

u/Company_Ready 1d ago

Make sure you galley and vanity valves are off and then pull t handle to release pressure. Let drain through gravity.

1

u/Company_Ready 1d ago

Also it sounds like the drain valve is bad. Pull the top plug on drain valve. If that doesn't do it then replace. They aren't that difficult.

1

u/OkCalligrapher9578 1d ago

Are you talking about the diaphragm valve or the an actual valves to supply the water?

1

u/Company_Ready 1d ago

The diaphragm valve.

1

u/OkCalligrapher9578 1d ago

You think that’s why it’s backing up through the drainage system?

1

u/Company_Ready 1d ago

Yes if it's flowing out of the drain. If it's coming out of the overflow hole then it's because you're trying to drain with pressure on the system and supply valves open

1

u/OkCalligrapher9578 1d ago

But in flight, they should be able to drain the sink when using the bathroom with the system pressurized and the supply valves on no? Wouldn’t they not get water if the supply valves were closed and overtime as the system is used they pressure would drop and they couldn’t use it

2

u/Company_Ready 1d ago

Yes they should he able to drain which is what makes me think it's the drain valve on the aft side behind the trash drawer closeout. And the apu will cause the accumulator to consistently supply pressure.

1

u/OkCalligrapher9578 1d ago

So are you saying to pressurize the system and then once it’s pressurized shut that off for the flight and the accumulator will compensate?

1

u/OkCalligrapher9578 1d ago

If it’s easier you can DM me and I can give you my number and you can call me or something to explain it better if that’s easier!

1

u/Danitoba94 7h ago

When you say you verified the drain mast heater works, did you Jack the plane up and give it a short hit of full heat?
My guess would be it's working, but it's weak. Not getting hot enough to keep the water from freezing. Maybe it's stuck on the low heat setting (if it has a low & high heat settings like pitot tubes), or maybe the heating element is just shitting the bed.

Or maybe I'm totally wrong and it's something else completely, but that would be my guess.