Bilge pumps wont turn off

I dont understand how one pump would trigger all the others. Never seen any boat rigged that way ad i dont see the point. Each pump should have its own float switch, on its own circuit breaker.

When you say switch, are you talkning about over ride, manual switch, or are you talking about circuit breakers?

One thing that has peed me off for many years is lazy engineers who clip off cable ties that wiggle down and stick under float-switches. Flat batteries and burnt-out pumps suck, just from an old cable-tie.

So instead of having one override on switch per pump you only have two? And instead fo turning on one pair of pump, one switch turns all four on?

That and builders not installing enough pumping capacity...

It sounds like a high water alarm float switch triggers all pumps. Let’s start with make, model, length and year.

Or a stuck relay controled by the alarm / all on float.

My guess is a defective diode in the alarm panel feeding back, or maybe wiring reversed when a new pump was installed. Could be the whole panel is bad. Is the alarm panel a name-brand unit? A diagram for that would be informative. The alarm panel might explain why overheating alarms go off with bilge pump activity. Not much heat generated by a running bilge pump.
Of, course, any information on the boat in question might help, as Capt J suggested.

Relays and diodes don't belong in mission critical circuits like bilge pumps. One feed to the float, one feed to the override on, a light. Ain't rocket science. Add a feed, light and buzzer to a high water alarm float.

While on the subject of bilges, we are doing another 2 day turnaround repower of a fastfisher. While we whipped the old engine out this morning, gave the engineroom a good clean.

Strange things that were found in the deep keel included the usual cable-ties, lost nuts and bolts, a nail-file, cigarette lighter and......... a complete Snicker bar!!!

Please guys, take care with your chocolate.

How did the snickers bar taste?

Gordon Ramsey has a special word for this, not for a family site like ours.