Leaky bilgepump hose, and cockpit drains.

prv

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I've replumbed KS's manual bilge pump (a Whale Titan) using this hose from ASAP: http://is.gd/8XVzq . I also used it to renew the cockpit drains, although I'm not happy with the strength of it for that application and am going to use something sturdier instead. In both cases, I've noticed that water is leaking between the hose and the tail it's clamped to. It's possible that I didn't do the jubilee clips on the pump up tight enough, but I would have done on the cockpit drains, which are also double-clipped. And yet there are still drips of water visible below the hose there. Under the bilge pump there is a definite damp patch, and again drips are visible at the end of the hose.

I'm wondering if the helical nature of the hose makes it difficult to seal. Is there anything I can do to improve it? Apart from this the hose seems ideal for the bilge pump, and I've already installed it in a mildly tortuous location. It is sold for the purpose, after all.

Slightly separately, as I said, I'm not happy with it as cockpit drain hose. It has to bend round a constricted space, so the flexibility is good, but it just doesn't seem robust enough for something that has to keep the sea out. The problem of buying this kind of thing online - it's a lot lighter than I expected because you can't fondle it before buying like in a shop. Can anyone recommend a type of hose that is strong enough to use below the waterline (albeit after a seacock) and yet is flexible? The old nearly-rigid green monster of a hose would be very difficult to fit now I've added a raw-water strainer.

Since I already have a basket in progress with ASAP I'm looking at this hose: http://is.gd/8XXPx but again I can't really tell how solid it is (and the ASAP site is frankly rubbish unless you already know exactly what you want). I'm also likely to be visiting Force 4 in Bursledon next weekend, but on their Web site at least they don't appear to sell hose. Pointers to decent hose anywhere else are more than welcome.

Cheers,

Pete
 
Hoses

Hi Pete I used similar hose in the past I now use clear fuel pipe ask local chandler or better still find a pipe supplier in yellow page I did all mine this year including there jubile clips for £15
 
Trouble with hose is there are so many sizes, I have replaced a few and added a few hoses and found the best way is to cut a section off the current hose and walk into a local pond supplier, they have loads of hoses, any hose that fits easily over the part its being clamped to is not a good seal, as said above some dont like clips, some are designed for differant types of clips. If you can slice off a mm of the part you are connecting a hose to even better.

The hose with wire running through like a big spring is to be avoided on boats it is very thin and even a clip can put a small hole in it.
 
Stand down on the cockpit drain hose - I popped into Machine Mart on the offchance on the way to work this morning, and bought some hose intended for the suction side of site drainage pumps. Definitely robust; hopefully it will bend OK. I am contemplating replacing the nylon fittings at the top end with DZR or bronze, though, as this hose could exert quite a lot of force and the current nipples are a bit marginal.

I still want to use ASAP's bilge pump hose for the bilge pump. I don't like just smearing goo on things instead of making a proper seal, but I do have a tube of special Loktite sealant intended for coarse plumbing threads which might do in a pinch. Must admit I'm surprised to have this incompatibility between hose sold specifically for bilge pumps and what is probably the most common bilge pump in the country.

Pete
 
I also used some of the ASAP's flexible bilge pump hose and had the same problem of it not being stout enough and the hose clips damaging it on assembly. In the past I've used the heavier clear hose with internal diagonal type nylon reinforcement. From memory I got it from a commercial outfit and it was cheaper than the chandlery - but still not as flexible as the lightweight ASAP hose.
 
I also used some of the ASAP's flexible bilge pump hose and had the same problem of it not being stout enough and the hose clips damaging it on assembly.

I'm happy with the robustness for bilge pump purposes, just not for hoses that will permanently have the sea level halfway up them. I don't think the clips have damaged it at all, they're just not able to seal it fully due to the spiral shape.

Pete
 
If you heat the hose in boiling water or with a hot air gun and assemble it quickly and tighten up the clips whilst it is a wee bit soft you will get a much better seal, plus it's easier to push onto the union.
Be careful not to damage the hose though with the clip when it is still soft.
;)
 
Have just renewed the hoses on my Whale MKX bilge pump,and renewed the valves. The new hose I got from Force 4 Chandlery at Bursledon is a neoprene hose with a nylon(?) thread reinforcing running through it. I had difficulty in making a bend that didn't flatten the outlet hose, and with hindsight I may have been better using the straightforward clear neoprene type. I boiled water and left the hose in this to get softer to pass over the flange, but the reinforcing then was a nuisance, however it did get there and I secured with a small ring spanner on the jubilee clips without cutting into the hose; using just a screwdriver would have been no good in the space available.
If the bends are not too tight I would guess that this hose would be suitable for cockpit drains as no pressure is involved, but I'd do them up tightly with the spanner headed circlips(stainless) double-clipped at the fittingssoftening the hose as above.

ianat182
 
If you heat the hose in boiling water or with a hot air gun and assemble it quickly and tighten up the clips whilst it is a wee bit soft you will get a much better seal, plus it's easier to push onto the union.
Be careful not to damage the hose though with the clip when it is still soft.
;)

That's what I always do -- with a hair drier, which cost about £6, and lives aboard. I reckon the hot air option is better than hot water, 'cos you heat the hose tail as well.
 
The problem with ASAP's spiral bilge-pump hose is that a normal hose clamp can only press on the spiral reinforcing. The material between the reinforcing isn't under any pressure and so the water can get between it and the hose barb. Since the reinforcing is a spiral rather than separate convolutions, there's a continuous path from above the clamp to below it, which water can follow and is. This is the fundamental design flaw of selling this hose as "for bilge pumps" and is what I'm trying to fix. I can't see that heating the hose or any other suggestions so far will make any difference to this specific problem.

My next plan is to "worm and parcel" the hose in way of the clamp, so that the clamp can also apply pressure to the material between the reinforcing. I'll probably just use some B&Q braided cord I have handy; this will probably crush over time but if I used something more resilient I'd end up with the original problem in reverse, as the new packing keeps the pressure off the reinforced part of the hose instead of the unreinforced part.

ASAP really need to find themselves a supplier of spiral hose clamps and offer them for sale alongside their spiral hose.

Pete
 
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