Here's a picture of the pump on our new Jabsco head. Look familiar? Well it is more modern looking, but the basics are still there and identifiable. In fact, there are graphics on the pump to help you understand its operation.
- The big black handle (only about half of which is shown in the picture, at the bottom) operates the pump. Like the Groco, you stroke it up and down to move things along.
- The flush/no flush valve, which was a hard-to-identify brass lever on the side of the Groco head, is now a big black flipper, with graphics under it to show what happens when it is positioned to the left or to the right. The graphics show that when positioned to the left, pumping will admit rinse water to the bowl, and when positioned to the right as it is in the picture, the bowl will be pumped dry.
Nevertheless, boat etiquette allows for the asking of operational instructions. If you are on someone else's boat and have discovered you have a pressing need, do not hesitate to ask for operational instructions. Heads are all a little different, and in some (the Groco, for instance), the flush valve may not be obvious. Experienced boat owners know this, and will be happy to instruct you on the operation of their head(s), and if fact may do so unbidden. No demerits should accrue to them for doing so, nor to you for asking if they do not.