Bilge Alarms

[CSR]

I had an assessor down on Wednesday coding my rib and he has instructed me to install a bilge alarm into my engine compartment. My question is - if I have an automatic bilge pump in my engine bay already A) do I still need an alarm? and B) do I need to change the automatic bilge pump to one with a float switch?

Many thanks in advance

[Erin]

Presumably a float switch wired into an alarm sounder is all you need. If you already have a float switch attached to your bilge pump it is possible to wire a sounder in parallel so that it sounds whenever the pump operates.

[willk]

Originally Posted by Erin

Presumably a float switch wired into an alarm sounder is all you need.

No help to the OP but vaguely topical:

MANY years ago I was asleep on a very small boat somewere out in the Red Sea. I was awoken at 0300 by "maintenance" noises and arose to find the skipper (Udo Fisher) poking around in the bilges.

"S'up Udo?"

"Notting, I hef vired ze ship's horn to zer float svitch"

"Why Udo?"

"Ach, zer iss som vater comming in, und I vant to get som sleep.."

So:

1. I slept (kinda) in my BCD.
2. She went into drydock two days later.
3. She was never relaunched.

[CSR]

Yeah that's what I'm thinking it needs BUT if I have a automatic bilge pump, do I need a float switch as they do the same job??

Love your story willk!!!!!!

[willk]

I'd have thought that you want an alarm that goes off when the water level rises above the existing pump, indicating that it can't cope/has failed. Surely an independent floatswitch and buzzer would suffice?

[CSR]

Thanks willk. That makes sense now. As with everything re coding, most of it doesn't make sense at all. I was coded on Wednesday and after reading the codes pack on the DFT site I spent almost £500 on items for my boat to get her up to scratch. The surveyor only asked to see 3 things that I bought so I could have saves almost £420.
Nightmare!!!!

[Erin]

Originally Posted by willk

Surely an independent floatswitch and buzzer would suffice?

Err, echo....

[willk]

Originally Posted by CSR

Thanks willk. That makes sense now.

Originally Posted by Erin

Err, echo....

No. I made sense

[CSR]

Of course you did Erin. Thank you very much for our reply too. Just trying to find a wiring diagram now.

[Erin]

Easy...

[willk]

Originally Posted by Erin

Easy...

...to forget to add a fuse

[Erin]

If your boat is sinking, I'm not sure a fuse will be much help . Joking aside, it also needs an isolator switch, and maybe wiring into the domestics rather than start batteries. It was just to illustrate how simple it is.

[CSR]

Thanks for all your answers guys. I've decided to buy a new pump as my engine is out just now so I may as well replace the whole lot while I can to save any hassle if the current one packs up in the future. I've bought a 1100gph pump with a float switch. I've also bought a separate float switch for use with the alarm. Does this seem reasonable?
Thanks

[biffer]

You've got roughly the right answer but installing a pump while you're engine is out is not wise unless you put some thought into it
Assuming your inboard. You should install your pump where you can get at it. No point having a pump you can't get at once all you're boats put together. What if it buggers up. You'll need to take the engine back out to get at it

[biffer]

You can add an alarm to the original wiring. When the pump comes on the alarm does as well. Simple enough

[CSR]

Hi biffer. The rib that I've got already has an automatic pump fitted below the engine, so as I have the engine out just now I thought it would be a good idea to just replace it to reduce the chances of it failing any time soon. The lowest point of the bilges is right below the engine so it's impossible to get at whilst the engine is in. My plan is to install the pump & switch as normal but have the second switch at a higher lever and connected to the alarm. If the water level rises to the second level the alarm will sound If I had the alarm going off every time the pump kicked in my neighbours in the marina might not be too happy when it fires up at 3am.

[wavelength]

We have float switch and bilge pump assembly in both engine compartments and both accomodation units under the floors. Also in there are bilge alarms completely seperate, and above the levels of the bilge pump kit. Tested by turning a knurled nut on the side of the alarm body which lifts the internal float and sounds the alarm on the panel. Had our inspection last week and having done the complete check procedure during the week before I had been under the accom floor via a storage cupboard with my **** up in the air for an hour or so getting a new float switch rewired into the pump cos it had been sticking, and one persons idea of curing that had been to cut the ***** wires! Repacked the cupboard and of course the inspector didn't check it, or anything else I'd sweated over during the week. But thats the idea perhaps...you don't know what he is gonna check and it makes you ensure everything is up to scratch. Also ensures that you know where everything is and how it works, or in some instances doesn't.

[biffer]

The golden rule for a good boat is make sure you can get at everything. The bits will always fail at the worst time.
There is a trick of mounting the pump with all it's bits on a pole and lowering into the deepest bit of the bilge and then bolt the top of the pole to whatever is handy. Usually transom. I've made some fancy mounts in my time. Curved. Straight. You name it.
The beauty of them is simple. Unbolt them. Fixed/clean put it back.
They will vibrate so make sure it is put in under tension. Less risk of the bracken failing

[martini]

Originally Posted by CSR

The lowest point of the bilges is right below the engine so it's impossible to get at whilst the engine is in.

With the right kind of pump, you could mount the pump somewhere accessible and use a hose down to the bottom of the bilge.

[willk]

IIRC, Whale have a self-priming pump for this application.