You will not get roasted here on Sunline Club, just ask whatever question you need help with. We are a friendly bunch.
The valves, great pic! Those "appear" to be the lift up and down handle type. I have never seen or operated one up close, but the older campers had lift up and down drain handles. Hoping one of our members with the older type will come in to confirm.
And you stated you dug out any mud dauber next, yes, for sure go under the camper and look up the drain pipe to make sure it is not clogged. That should not affect the valve handle operation but will the draining operation.
Good luck and let us know how you make out.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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