People who do their own plumbing really have to pay attention. Really. Since I’ve rebuilt the Henderson pump, I thought it would be satisfying to finish the holding tank overboard circuit I began several years ago. With that in mind, I set about to install the Henderson back into the place I had prepared for it.
The pump is most easily installed in this place by removing the sink from the countertop. That done, it’s fairly easy to align the mounting holes and fasteners and make the pump connections. I previously rebedded the sink with a sealant that was not too aggressively adhesive. It came up readily with gentle pressure.
Installation of the pump, fasteners, hose attachments were straight-forward. The actuator socket aligned just as I remember from several years ago.
Some of you looking at the this may detect a flaw in the installation. “Flexible corrugated tubing?” you say, with doubt furrowing your brow. . . “Isn’t that bilge pump hose?” It is indeed bilge pump hose. The reason I used it was because white sanitation hose would not make the bends that I needed it to make. And it may well prove to be impractical, as I found later that I had trouble getting it to make a water-tight seal against the pump fitting. If this proves to be a persistent condition, I’ll have to come up with another solution, because not having a water-tight fitting where waste transits is a non-starter. But up to this point, I was unable to test the fitting.
I tested the pump. Good news: The rebuild restored its pumping function – no problem. But, there was an issue with the installation. The design of the Henderson pump is such that it allows assembly to accommodate a number of different orientations. You may notice from my previous post that the pump body is fastened together with eight sides, corresponding to eight screws holding it together. This geometry allows the installer to rotate the top half of the pump body so that it fits on any one of the eight sides, thus changing the angle of the inlet and outlet (which are opposite each other on the pump body). Very convenient and clever. However, the connecting hoses must be kept track of. Yes, just let that sink in for a minute. . . It follows, then, that if the hoses are not labeled, then connected in reverse of what was intended. . . hmmm. . . Unexpected results ensue. So instead of pumping water OUT of the holding tank, I was pumping water INTO the hold tank. Actually, I’m not sure I’ve reversed the inlet and outlet hoses. It may be a routing error at the Y-valve. I haven’t had time to dig back into it yet – just long enough yesterday to determine that the way it’s set up now does exactly the opposite of what I want it to do. And somehow I tweaked my back yesterday while plumbing in the wrong direction – so now I can move with only the most careful and deliberate motions, which means of course, that I can’t get back on the boat right away to sort this out. Hmmm. . .