HOC member login

Message Board

Message board > Miscellaneous topics > Bilge pump switch

Message 10 of 10
Posted by member Terry Asquith on Friday 14 May 2021

Pump 1 rated 800.
After much probing and testing I identified part of the problem as corroded connections on the switch. These were remade and, wow, the wiring was almost as you said it should be. The exception was that the power input cam via the battery isolator, so no power on shutdown. This looked to be the original wiring loom.
Various options but eventually I went for the simplest which was to disconnect the input to the "Automatic Bilge Pump" fuse on the fuse panel and replace it with a wire direct from the positive terminal of the battery. This provided a fused permanent supply. Simple but cost a good deal of gymnastic scrabbling and squeezing around the engine bay. Not good for a fat old bloke. Why the fuse panel has to be in an unreachable dark corner is a mystery, still I did discover there was a fuse for a shaver socket, I just wonder where the socket is...
Pump 2 rated 1100
This pump is defunct. It claimed to be automatic but the test button did nothing and immersing in a bucket of water made no difference. The connections are another mystery, there are 4 wires neatly wrapped together in tape at one point reducing to 2 at the pump. Where they come from and how they are controlled requires further scrabbling.

Add your comment

Message 9 of 10
Posted by member Terry Asquith on Friday 14 May 2021

Problem resolved. The 15mm plastic pipework had pushfit connectors of the screw down type and one was missing an olive. The pipework had also been secured back against the bulkhead to cables and other pipework forcing it to enter the tee at angle. All bad plumbing practice. The tee has been replaced by a different make and the pipework eased. Tested OK so all should be good.

Add your comment | ^Top

Message 8 of 10
Posted by member Terry Asquith on Tuesday 11 May 2021

Thanks for that Peter. I've drawn a diagram and I can now see how it should work. All I have to do is work out what the wiring I've got is actually doing. It's 14 months since I've seen the boat so I'm really starting over again.

Add your comment | ^Top

Message 7 of 10
Posted by member Peter Cox on Monday 10 May 2021

Welcome to the mysteries of bilge pumps!
Each of pumps should have its own switch at the helm.
Just dealing with one pump for the moment and assuming you have a float switch in the bilge:
The negative from the battery should go direct to the pump unless the helm switch is double pole, which I doubt.
The positive from the battery to the helm switch should be always live, ie it doesn't go through the battery isolator, so you can turn the other services off when you leave the boat but leave the pumps powered in auto.
The helm switch should have three positions: off, auto and (needs a continuous press) on.
Off interrupts the positive to the pump.
On connects the positive direct to the pump (bypasses the float switch) to run the pump.
Auto connects the positive to the float switch; with no water present the float switch does not send positive to the pump, when there is water, the float switch connects positive to the pump and the pump runs.
The red light on the helm switch should glow when the switch is in auto.
When in auto, test the whole set up by manually lifting the float switch.
There should also be a warning buzzer when the pump is running.

Add your comment | ^Top

Message 6 of 10
Posted by member Terry Asquith on Monday 10 May 2021

Another related question. I have two pumps fitted: one centrally under the engine, the other on the stbd side. Both seem to have float switches and neither pump seems to work. The wiring for the boat is a mess with wires apparently added or left redundant by previous owners so I'm not sure how these pumps are connected. On the instrument panel is a 3 way switch labelled bilge pump. The incoming wire is live but nothing happens when it is pressed. My question is how should it all be connected, what is the ideal layout?

Add your comment | ^Top

Message 5 of 10
Posted by member Richard on Saturday 6 October 2018

I am thinking of one of them aircraft style switches with the red cover so you have to purposely lift the cover to operate the switch

Add your comment | ^Top

Message 4 of 10
Posted by member Michael Williams on Friday 5 October 2018

Our Hardy 25 had a bilge pump fitted retrospectively. We deliberately positioned the switch away from all the other switches for this very reason. One has to deliberately reach for the switch and one could not inadvertently switch it off when closing other systems down. I suspect Richard is correct in worrying what position his insurance company would take had the vessel flooded while the bilge pump was switched off.

Worth repositioning the switch ?

Add your comment | ^Top

Message 3 of 10
Posted by member Richard on Monday 1 October 2018

I suppose if you have oil in the bilge then maybe its a bad idea for it to be on auto, but to me preventing the boat sinking is right at the top of my list.
I was miffed when I went down the boat and noticed I had switched the bilge pump off by mistake, so in the two weeks I hadnt been on board the boat was at risk , say it sank and the insurance comapny found out the pump was in the off position, that could be entertaining!

Add your comment | ^Top

Message 2 of 10
Posted by member keith Lathwell on Monday 1 October 2018

I would suggest that perhaps the switch functions are:
1) off
2) auto
3) on
There are plenty of situations where you wouldn't require the bilge pump starting on auto.
Rgds Keith Lathwell

Add your comment | ^Top

Message 1 of 10
Posted by member Richard on Monday 1 October 2018

* On our Hardy 27 there is a dash switch for the bilge pump, nothing unusual in that I hear you say, but it has three positions
1, off
2, auto
3, manual
Now my question is, what is the point of posiiton 1, ie off? as surely you want it on auto all the time and manual to test it every now and then.

Add your comment | ^Top

You must be logged in to post to the Hardy Motor Boat Owners Club message board. Click here to login in. If you’re not yet a HOC member then why not join us today?