I'm a complete newbie to the wonderful world of RVing, but I'm not so new to life or online discussion groups
So, I hope what I post here will be of some value to others over time and I offer it by way of making a contribution to the forum which has in just a few short days since joining been of true value to me.
I took my maiden voyage in my new-to-me, albeit used, 2011 Coachmen Freelander 30 QB just the other day. (I've named her Charlene, BTW, in a nod to John Steinbeck's book Travels With Charlie.)
Anyway, upon returning from my trip I noticed a little moisture on the asphalt below Charlene. A quick glimpse revealed a leak from the 3" Valterra Bladex valve under the black water holding tank. I also noticed that one of the four bolts that attaches the valve was missing and the other 3 were loose. After replacing the missing bolt and snugging up all of them the leaking almost, but not quite stopped.
So, I decided I would replace the valve. I could have decided to replace just the gaskets, but if it turned out the valve needed replacement too it would be a whole major hassle to undertake all the driving to my not-so-local RV shop, my not-so-local RV storage yard and home to buy and install the valve after already having removed the old one once. It would be worth the $14 price of a new valve (which includes gaskets and bolts) just to avoid all the potential hassle of not doing so in the first place.
Upon arriving home with the new valve and opening the package I noticed there were gaps on either side of the blade which made me wonder if it was defective. I mean, how would a blade valve with holes in it do what it's intended to do? (I said I was a newbie. Ha!)
Rather than bug everybody at IRV2 and possibly receive differing opinions about the normalcy or not of this condition I contacted Valterra directly. Believe it or not I actually got differing opinions from them! The first opinion was that it was not a normal condition. This opinion was voiced by the person that answered the phone who saw the attached photo. Later I got a call from Kevin--who I took to be more senior in the tech department--that this is a normal condition. So, for others that may have the same concern as I did, about gaps on the sides of the blades, there's your answer, assuming, of course, Kevin was correct.
I had some other questions which I posed while speaking with Kevin of Valterra (kind of sounds like some sort of royal title when put that way: Kevin of Valterra… LOL).
I asked about using vaseline to hold the gaskets in place during installation and to condition them. He said no. He said to use a silicone based lube if anything at all. (The rep with whom I'd spoken previously said the gaskets were made from santoprene and buna, in case you're interested.)
I also asked about commercial and home brew valve lubricating products, the kind you add to the black and grey holding tanks. He said he hadn't tested any of them, and as such could not endorse any of them. He seemed to lean--and this is my personal assessment of his position--toward the don't-bother-with-them camp.
I asked about lubricating the shaft. Obviously these can weather with time and small particles of dirt and debris can adhere to the shaft and infiltrate the channel in which it rides thereby causing stiffness or stickiness. Again, Kevin recommended a silicone based lube. He said not to use WD40.
As to proper care and maintenance of Valterra Bladex valves, there really isn't much else to do beyond lubricating the shaft if it develops resistance. That's my recollection in regard to my conversation with Kevin.
When it comes to replacing either the gaskets or the entire valve, sometimes gaskets are enough. The condition of the blade, or paddle as Kevin called it, needs to be assessed by visual inspection. I think trying to describe what to look for would be beyond the scope of what can be accomplished here, at least by me, other than to say look for wear and tear that might interfere with the operation and effectiveness of the valve.
I'm attaching two photos: one of a Valterra 3" Bladex Valve, marked to show the gaps to which I referred above; the other is a shot taken at Henry Cowell Redwood Park in Felton CA. It was very near to the Santa Cruz Redwood RV Resort where I parked Charlene during my maiden voyage. That's me in the photo.