Hello Michael,
I may be able to assist you (or offer suggestions) with a few of your points.
1. I'm assuming that your current manual bilge pump (whaler) discharges water out through the transom.
Most probably not a bad idea to leave all that alone and fit a new discharge point along side.
A couple of questions: Do you normally ever get water in the boat? When would you likely get water in the boat
or this only in case you have a failure of a fitting etc? If a failure occurred and you were not there, is there any way
some sort of an alarm would be heard by near-by boaties or residents?
The reason I'm asking this is my boat only ever had a manual bilge pump. Checking for water in the bilge was one of my pre start checks. If there was water in the bilge, I would want to know where it came from and why. If you did have a failure and you weren't there, an auto pump would only run until the battery went flat !
If you feel more comfortable having one, there are 2 options. One, seperate pump and switch-this allows you to mount the pump low as you can then mount the switch at a height that you best see fit. Option 2 is a combination
switch and pump. The best brand is Rule (American). The pump must be readily accessible so that the filter can be cleaned on a regular basis. All connections in that area should be soldered joints with glue filled heat shrink over them. Wiring for the pump should by-pass the Master Isolator so that it is the only thing "alive" when you leave the boat. Therefore, make sure this wiring is Marine Grade 4mm twin in convoluting tube with lots of fixings so that is well and truly out of the road of ever being damaged!
I think I've banged on enough on this one, I can answer more of your questions if you like!
Regards,
Maurice.