Interesting wiring tactics

[Doodie99]

So I have owned my Mark 1 for about a month and still discovering how some things are wired. It has two bilge pumps but only one float. It took a while to figure out how the second one was wired. I finally figured out yesterday that the power for it comes from the fresh water pump circuit. It has a manual switch above the fresh water pump to turn it on. I guess the its good to drain the last 2 inches when it's out of the water but useless for most other times.

 

[RT Firefly]

Greetings,
Mr. 99. Agreed. Not much use BUT do they have separate outlet hoses and/or are they in the same sump? Not terribly difficult to add another float switch, I expect.

 

[ksanders]

Having a manual operated and a automatic operated bilge pump serving the same sump area is a good idea.

I would have the manual one on its own breaker though.

 

[Doodie99]

The main pump is manual/automatic. This back pump is a small pump that is completely separate from the main one. The switch is a toggle switch below deck near the fresh water pump. I do like having the switch there to empty the bilge on land but it would make sense to add an automatic switch option too. Since when under way all the water heads backward.

 

[ksanders]

The main pump is manual/automatic. This back pump is a small pump that is completely separate from the main one. The switch is a toggle switch below deck near the fresh water pump. I do like having the switch there to empty the bilge on land but it would make sense to add an automatic switch option too. Since when under way all the water heads backward.

My Bayliner was OEM equipped with two bilge pumps in each location.

One automatic, one manual. Both separately powered, with the automatic having a indicator light on the helm when it operates.

 

[psneeld]

Not sure if I ever had a bilge pump or serviced or installed one that didn't have both a manual and auto (switch/float).

Not sure why you would not have both options on every pump.

Unless a temporary hookup.

 

[Solly]

It's probably a low water pump to get the last bit of water out. On my Mk III the bilge pump sits on a fiberglass 'bridge' a good 2 inches above the hull. Leaves a good bit of water behind when the float shuts it off. Dumb. Nice to be able to get the rest out with another pump. I added one with a built in float switch to get more out. Sits on the hull.
FWIW on mine somebody wired the main pump so you can throw a breaker on the 12v panel and it comes on manually.
Best practice is to have all bilge pumps wired directly off the biggest battery bank with proper fuses inline. That way you can't accidently shut the power off.