Theis,
Thanks, that was very helpful. The whale pump that I am planning to install will take either a one-inch or one and a half inch line. It mounts to a bulkhead by four bolts provided by Whale. It appears that an installer has two options in that there are two sets of our boltholes in the body of the pump.
I am going to assume that you mounted yours on the inside of your cockpit locker so that the bolts for the flush mounting pump go through a backing plate and then through the fiberglass cockpit wall. Did you feel that was sufficient, or did you build a little shelf in the cockpit locker for the pump to sit upon and utilize the other four holes to secure the pump to that shelf?
Secondly, how did you seal the 3.5-inch hole in the cockpit wall? I have now purchased a Whale urchin manual pump, and it comes with a formal looking flip up cover that hides the external mounting ring. I suppose that since the diaphragm is rubber, the best thing would be to bed the ring with silicon. Any thoughts? And does yours leak?
Finally, I selected the Whale Urchin rather than the Whale Titan because the Titan takes a one and a half inch line, and I have not found a secure one and a half inch fitting to go through the watertight bulkhead between the cockpit locker and the lazarette locker. I have a one-inch fitting, and so I selected the lower capacity urchin. By the way with a similar capacity Guzzler manual pump I can pump half a bilge full of water completely dry in two minutes. I am interested in what sort of leak-proof fitting you used to get a one and a half inch line through the bulkhead between the cockpit and lazarette lockers.
There is no question that a Rule 2000 pump would be a great asset. However, I would still want a manual pump in the cockpit.