Bilge pump hose selection

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Rogerh

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Joined
Aug 27, 2013
Messages
724
Location
USA
Vessel Name
At Last
Vessel Make
1990 Jefferson 52 Marquessa
Hi everyone,
I am in the process of replacing all my hoses on our 1990 Jefferson Marquessa MY. The hoses for the the bilge pumps are 1 1/8 inches. The hoses on there are totally shot but they lasted for 23 years. Since these are very difficult to get to for the runs I want to replace with something that will last for a very long time. Does anyone have recommendations on what hose to use? I have researched with various companies but it seems bilge pump hoses do not come in this size very much and if you find them I am not sure which type to use. Please advise. Thanks much!
 
I added a 3700 GPH pump and just spent the money to put the white sanitary hose on the system. I cant imagine it ever needing replaced again..
 
for the big boy bilge pumps...I recommend using the best as they are a line drawn in the sand that you want to take seriously. Because big hose is sometime difficult to work with and you want the shortest, straightest runs possible...a combination of pipe and hose may be appropriate also. But any good grade marine hose is acceptable in my book..the smoother the inside the better.

For most bilge pump though I have started using the basic cheapo plastic stuff because it's cheap and easy to run. As long as you are careful and install it properly, the splitting issue isn't as great and if I need to replace it every 5 years or so..the cost and ease of working with it makes it worthwhile in my book. Granted I'm not happy about some flow loss due to the corrugation...but if I'm running smaller bilge pumps rather than monsters...then a small percentage loss can't be all that important anyhow.
 
Thanks for the suggestions. Do any of you hav experience with the Trident 147 as far as longevity and flexibility? This is going to be very difficult to run so I want to make sure I only need to do it once if at all possible. I have 4 pumps to install new hose on.
Thanks
Roger
 
Try to get hose that is as smooth inside as you can find, to increase discharge volume.
 
The biggest issue with bilge pumps is head pressure. If you look at the (Rule) tables you will see that the height you have to pump will quickly halve the amount you can move. The hose has little to do with it. Make sure you install the biggest pumps you can fit in, unless you're just looking for a specific one for a specific purpose, such as a shower pump or for a stuffing box chest.
 
Xsbank - "install the biggest pump(s) you can fit" - I am looking at the Rule Gold 3700. Do you have any larger pumps I should consider? I currently have a 2200 and a 500 which does not make sense to me so I am looking upgrade at least to the 3700.
thanks
 
Something happened to my post - check your voltage and head to determine your output, plus make sure the pump is wired with the correct polarity or you lose 20% right off the top.
Look at how voltage varies the output of the pump. When you really need it, are your engines running or are you on battery? How long will your battery support a 20 amp drain?
Your 3700 gal per hour with an open pipe; at 13.6 amps at 3.35 head puts out only 3100 gals per hour. At 12 volts and the same head it's 2600 gals.
At 13.6 volts and 6.7 feet of head, it drops to 2500 and 2100 gals!
You really need to look at your boat, your electrical system and imagine the flow from a broken through-hull or a faulty transducer, let alone a hole in the hull, then figure out how much pumping capacity you need.
 
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A 2" hole, 4 feet below the waterline, flows 157 gals per minute (US gals) which is 9420 gals per hour, which will dwarf your "3700" pump. You would have to actively fight a leak like that because you could not keep up with it with pumps. Your boat is big enough that a Honda trash pump would be a reasonable addition, they are about $500 and my memory is niggling me that they are about 8000 gals per hour?
Your 500 pump might make a good shower pump...
 
The white pvc flex hose used for swimming pools and jacuzzi's, or the similar (same?) hose used in dairy milking machine/handling operations are smooth bore and less expensive than the marine sanitation hose. I used some of it in conjunction with solid PVC. Seems to be holding up very well.
 
Rogerh, all three of the hoses I recommended have smooth interiors. The 147 is a very good hose that should last a very long time. I think the 144 is a little more flexible.

HenryD, Rule also makes a 4000 GPH pump. If you install the 3700 you'll need to use 1-1/2" hose. The 4000 requires 2" hose. Both of these hoses can hold a lot of water that will flow back to the bilge when the pump shuts off. This can cause the pump to cycle on and off. I recommend mounting a small pump, 500 or 700 GPH, that uses 3/4" hose low in the bilge as your primary and the big pumps a little bit higher. The small pump will handle the usual sources of water and with luck, the big pumps will never be needed.

I don't know what engine or engines you've got in that boat, but engine cooling pumps larger that 1" can move significant amounts of water and it's very easy to rig them for bilge pumping.

Even better is a big belt driven pump attached to the engine.
 
The above contributions underline the importance of having indicator lights at the helm positions which tell the helmsman when the bilge pumps are running. The behaviour of the lights (intermittent, steady-on etc) gives warning of a dripping stern gland, a blocked pump inlet or a broken hose. If the first sign of a major leak is the engine stumbling, then the engineroom is probably half full of water. Under these circumstances, locating the leak and fixing it becomes immensely difficult and sinking can well result.
 
:A 2" hole, 4 feet below the waterline, flows 157 gals per minute (US gals) which is 9420 gals per hour,:

A bellows blowout from some ceramic seal setup that has not been serviced in time could easily be a bigger leak!
 

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