Bilge pumps & non-return valves

Stemar

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I have a 360GPH Rule (I think) bilge pump under the cabin sole in Jissel. The pipe has a non-return valve an inch or tweo away from the pump The arrangement is about a year old. Now, Even when there's water there, turning the pump on doesn't do anything until I suck on the through hull, (carefully /forums/images/graemlins/tongue.gif!), when the water starts to flow.

Is the valve faulty, or is the pump not really up to it? Due to old oil leaks, my bilges are a bit manky and recent filter & fuel line problems haven't helped. Should I expect a non-return valve to survive contact with oily water?

My local swindlery has a low profile pump (Whale brand, from memory) for about £20, again, from memory. This would actually do a better job of emptying the bilges, 'cos I could get it into the middle of the bilge, while the current one has to be offset a bit because of its height, but is it likely to be have more umph than my current pump?

Apologies if this is a bit rambling - I'm a bit brain dead after a hard day!
 

Channel Ribs

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While bilges are not the most delightful places for a rumage, it may still be worth getting the bits apart and seeing how they cope. It may well be that a bit of a flush through will get everything us to speed again, if not you will soon see which part is duff.

Be wary of low profile bilge pumps, some are very weak indeed.

Also, take care getting rid of the NRV, it may be there because someone decided not to put a loop in the pipe and it is the only thing stopping sea water coming in at certain angles! /forums/images/graemlins/shocked.gif
 

Stemar

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Snappies don't like green water on the windows - and SWMBO likes it even less, so I try not to do it, but we did manage it the other day in a gust. There's no way I could get a loop high rnough to keep water out doing that. I do have a sea cock, but with blond hair (what little I have left) and advancing age, it's not unhead of for me to forget to close it when we go out. I reckon the, or at least an NRV needs to stay.

Poking around in bilges doesn't bother me too much - if you've unblocked heads or changed nappies, bilge water's no problem!

I suppose it comes down to a few simple questions:

1. Is there a special grade of NRV that wil stand up to oil without the rubber getting sticky

2. Do I need a more powerful pump to force the water through?
 

Channel Ribs

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[ QUOTE ]
1. Is there a special grade of NRV that wil stand up to oil without the rubber getting sticky

2. Do I need a more powerful pump to force the water through?

[/ QUOTE ]

1. Both Whale and Index do a valve which work in a similar way - the former is tried and tested to be sound over time and sludge. /forums/images/graemlins/blush.gif

2. The pump sounds up to the job, but fit the highest capacity you have room for. After my experiences with a lost shaft I was tempted to throw out the inboard and fit a diesel salvage pump in it's place! /forums/images/graemlins/tongue.gif

Come to think of it, the salvage pump routed out through the empty stern tube may have yielded good propulsion....

*Malthouse has now left himself wide open to abuse from Kawasaki* /forums/images/graemlins/frown.gif
 

FAITIRA

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Re: Bilge pumps & non-return valves

Be careful about throwing out the nrv, I have just put one in the Nic 32, in the shower drain line, because if one forgot to close the seacock, there is nothing to stop the water flowing back, similar situation as yourself! Re the pump, it sounds like the lift capacity is not sufficient, though it should be, my 500 is lifting about 700mm no bother from the shower tray. The nrv will be unaffected by oil I think.
 

Kawasaki

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Re: Bilge pumps & non-return valves

I was going to reply anyway.
"Brain Dead"?
"Rambling"?
"Hard Day"?
Hhm, reminds Me about a certain Swindler.
Fitted a NRS.
"What's an NRS?" I hear You say.
"None Return Shaft"!
Salvage pump routed out the empty stern Tube etc etc /forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif
 
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