WOW, 2 grey tanks would make sense! Yep, hand fed the snake and never met resistance...so WHERE is the valve for it?????
Well T H A N K S to ALL on here you got me thinking. So first thing I did was do a walk around as the valves are marked. OK, Black and Grey, 2 valves, that is it! But as my Grey tank is dry since its in my driveway I opened it up and shined a light...yep, it goes straight to the grey tank...but...WHOA, what is that I see about ¼ down on the right (toward the rear of the fiver, that is CLEARLY a connection!!!!!
So I walk along toward the rear, no label, no valve!
Then I think, lets check the the board in the hallway. YEP shows 2 tanks, so I push the button to get a reading on Tank 1 = EMPTY, then I push 2, FULL!!! AHA there are TWO tanks on my unit!!!
Go back outside and look under the slide and yep, there is a valve. I pull and water GUSHES out the low point drain!
PROBLEM SOLVED and a THANKS to all here for you help, suggestions and just making me think.
Then I found this on line (not on Jayco):
2016 Eagle HT 27.5 RKDS (my exact unit)
Gray Water Tank (gals.): 32 - 1/2
Gray Water Tank (Secondary) (gals.): 32 - 1/2 -
See more at: 2016 Jayco Eagle HT 27.5RKDS
Talked with 3 Jayco Service people, none of them knew, dealer told me the 2 Grey tanks were only on the larger units not on the Eagle HT series.