Need ID for gasket material found in BT flush

[DT57]

I found this gasket material when I flushed the black water tank using a hand wand. The dump valve on tank is not leaking so I think its possibly in the toilet stack and I've gouged it out from somewhere there. The top flush valve in the toilet stack seems to be intact with no unusual odor.

Is there a schematic drawing or some way to ID the replacement gasket I need, and
How big of a repair job am I looking at?

[GCinSC2]

DT57,

Greetings from sorta near the Track too Tough to Tame, AKA The Lady in Black, S.C. For the non NASCAR crowd that's Darlington and today is RACE DAY! Nope, I'm not going.

The grey stuff looks like Butyl sealant. I just used some last year on tank valve R&R. Not sure about the black, Silicone RTV??? I had a time finding that stuff, found it at an RV store as skylight sealant. It stays flexible a bit like used chewing gum.

But how about a slow fill test with clean water of the tank and see if it's an actual issue or left over from mfgr of unit?

Access to the no fuss flush likely means time to find it's general location then make an access hatch in the pan keeping in mind might as well make it big enough for valve service if ever needed.

Gary

[DT57]

Yes this stuff is very flexible almost jello like. I'll try a tank fill and check for leaks. I have a camera scope too so will try that.
Thanks GC.

[GCinSC2]

That butyl is what seals the valve “stem” into the tank. It’s a slip fit with clamp. The butyl is the flexible sealant making it water tight. That might be excess that found daylight.

[Brainodo]

I found the same sort of stuff, blocking my black tank valve.
https://www.airforums.com/forums/f44...on-210904.html