Mick, I realize that this is a DIY column, but I am considering the purchase of a drink holder/catch-all that installs using suction cups. Do you have any opinions on these? Ever put one on a boat? I do have the tools and skills to install a traditional unit, it’s just that I’d rather boat than turn a screwdriver! John McHenry Fort Salonga, New York
A: Yes, the bilge pump will be hot-wired at the battery switch. Check to make sure the automatic switch is not getting stuck in the “on” position. The A: Hi John. I have no experience installing these suction-cup accessories, but I do have an opinion from my time aboard Editor-in-Chief Kevin Falvey’s boat. He has a few suction-mounted accessories at his boat’s helm, and they stay secure in coastal waters. Falvey reports that the suction cups need to be replaced every three years or so, because they eventually lose grip. He told me the suction cups are available alone, so there is apparently no need to replace an entire cup holder or storage box. float should be pointed aft (hinged forward) to avoid going on if the bow gets lifted or the boat leans to one side. This is proper installation, even for a boat that is trailered or stays in the water, because running in waves might turn the pump on. It could be an improper float-switch install.
Also, is there any water left in the bilge when the boat is hauled? If so, make sure any wiring is not in that water.
As for the radio, yes, the memory draws a small amount. Here’s a simple test you can try first. Turn off all switches and all devices. Turn off the batteries. Now start turning things on one by one. If any of them (except the bilge pump) come on, focus on that circuit. It could be that the switch is wired wrong or there’s a bad ground on that circuit.
If that does not turn up anything, you need to get a digital multimeter and, with the battery switch off, test each and every device on the output side of the switch for that device looking for voltage. There may be a minimal amount (insufficient to power up the device) but enough to drain your battery over time. There could be wires touching each other or terminals of different circuits touching each other. Or a bad switch.
Patience, persistence and detective work will pay off, if the bilge-pump install checks out and the simple test of switching things on one at a time fails to turn anything up. Good luck!