Diaphram Bilge Pump - Best choice?

[PamlicoTraveler]

We have a Jabsco diaphragm pump (this one)

This was put on by a PO long ago and I am wondering if it is best for our situation.

The pump sits above the water line and and a hose goes to the bottom of the bilge. This is our primary pump, and there is an Ultra pumpswitch at the bottom of the bilge to turn on and off the pump.

So the question is, is a diaphragm still the best option for that scenario? Obviously it has to pull the water up 2 or three feet and then pump it overboard.

The pump just broke and we replaced the membranes and it still doesn't provide suction, so I am thinking of just buying a new one just like it. But if there is a simpler pump that can do that job I would love to know about it.

Any thoughts?

[Unicorn Dreams]

It might have been factory installed. My boat has 4 of them. 2 bilge, 1 shower sump for both heads, 1 fresh water pump.
Have had to replace diaphragms, but my pumps are 35 yrs old. The reason they were used, I believe, is that they will lift higher and push water further and higher.
Check suction hose to see if it's leaking air...

[cal40john]

This pump is only 6 gpm. Good for drying the bilge, not useful for a real leak. The PO put one on my boat I believe because the bottom of the bilge is nearly in-accessable. So the pump is up where you can work on it. Centrifugals which have much more pumping capacity have to be at the lowest level that you want them to pump down to.

I added a 2000 gph (30 gpm) centrifugal pump up higher in the bilge on top of the ballast where I can reach it and clean it. It also has an alarm so I know when there is more than small amounts of water in the boat. IMO while 30 gpm is better, it is still not adequate. I am still working on what my next addition will be, maybe an engine driven impeller.

John

[rebel heart]

We have an Edson 30 portable / manual pump:

Rebel Heart - Sailing, cruising, liveaboard blog and website - Eric's Blog - the manual bilge*pump

We have a friend right now crossing the Pacific, and both of his bilge pumps fried out and he's left re-routing the shower sump pump to keep the bilge empty. If that fails, it's bucket/cup time. Re-routing the sea water intake from the engine doesn't seem to possible underway and the hose won't reach down that low from what I've gotten from him.

The Edson isn't cheap ($1000) but it can suck up and spit out a golf ball sized obstruction, and you can literally pump for hours. Just something to think about if you're looking for a last ditch way to suck tons of water out of the boat while someone stops it from coming in.

[skipmac]

My experience with Jabsco diaphragm pumps I have likes and dislikes.

Likes

- run dry, no damage
- self priming
- reliable (one exception, see below)

Dislikes

- very sensitive to any small piece of trash. Will get into the valves and the pump basically stops pumping. Definitely use an in-line strainer but even that can pass little bits that will get into the pump.
- not exceptionally loud but not exactly quiet.

[btrayfors]

Have tried 'em all over the past 30 years. You name it; I've tried it and/or installed or troubleshot them on client's boats.

Only one I'd have on my boat...and I have 4 of them....is a FloJet (not ShurFlo). Quiet, reliable, reasonable flow rate. Good for all kinds of things (bilge pump, pressure water, sump, etc.).

ITT bought 'em a couple of years ago and immediately doubled the price. Still, even at their prices they're a good investment...at least until ITT fools with their design (read "cheapens") as they're prone to do.

BTW, I have two of the Ultra switches...a Jr and a Sr....plus their high-water alarm. These go well with the FloJet pumps.

Cal40John is right about a dewatering pump in a serious ingress situation. I have a 3,000 GPH pump as a backup, but even that wouldn't be enough in a really serious leak situation.

Bill

[PamlicoTraveler]

Bill (btrayfors) - wondering if that type of pump will lift like a diaphragm. Our suction hose goes down ~3ft to the bottom of the bilge and it has to pump up above the waterline. That's why I was wondering if there was originally a reason to have a diaphragm pump instead of another kind. It seems kind of old fashioned with the belt etc. Maybe the new ones are better than they used to be. I am kind of curious why they had the diaphragm pump at all? Any idea? Thanks

BTW...ITT also owns Rule and Shurflo, so they've kinda got a lock on things I guess.

[btrayfors]

The FloJet IS a diaphram pump. It has four small diaphrams. It does NOT have a belt (and those pumps with belts are pure crap...I've pulled six of them off of my own boats, and many off of client's boats).

The FloJet will pull a 3' head no problem. Mine pulls upwards of 6'.

Bill

[PamlicoTraveler]

Originally Posted by btrayfors

The FloJet IS a diaphram pump.
The FloJet will pull a 3' head no problem. Mine pulls upwards of 6'.

Xcellent...Thanks!

[CarlF]

I also love flojet pumps but don't consider them ideal for bilge or sump duty. In my experience, they are too sensitive to crap.

The Edson is a manual pump. It is in a league of it's own. You could bail the ocean dry with the thing. Your great grand children will use it. But it is very expensive.

The Whale Gulper 320 and Jabsco 50890 both will prime from 10ft and use a simple cam diaphragm. Very hard to clog. Quiet and rugged. I've owned both and been very happy. They only pump about 5 gallons a minute but that's more than your current pump.

Jabsco 50890 Series Filterless Waste Pump

Whale Gulper 320 High Capacity Shower Waste Pump

While you're at it. Consider installing a 2nd high capacity pump like a Rule 3800 for emergencies mounted a foot above the sump. Hopefully, it will always stay nice and dry.

Carl

[delmarrey]

This is what I use as a back up (28 gpm, as long as you can last!). If one loses power or your motor this is your only choice once the batteries are dead. The removable handle comes thru the upper deck in my cockpit, right by the helm.

If one gets enough water in to flood the motor and batteries your sunk unless you have a bucket brigade. It takes time to stop the flow if one is holed. and the deeper you go the faster it comes in. Electric is fine as long as one has the power, but it's nice to have a backup.

[S/V Alchemy]

I've got one of these as a Hail Mary pump.



It's the thing I let go of when we step up into the liferaft!

+1 on the Flojet. I have one for the pressure water and find it very reliable. I have a Rule 3700 in the main bilge, but I think I can do better.

[SV Demeter]

I currently have a deep sump with a jabsco diaphram bilge pump rated at 480 gph using a strum box and an inline strainer. I rarely ever have a drop of water inside my boat because of deck stepped rigs so this pump never sees any duty. I also have a large manual whale pump with handle at the helm. I have an area above the sump in the bilge where I would like to mount a big centrifugal style pump with a float switch tied to a high water alarm but am not sure how I would plumb the discharge from this pump. I dont really want to tie it into the discharge of either existing pump because that would require a check valve which is a big no no on bilge pumps in my opinion. I also dont really relish the thought of drilling another hole in my hull. Suggestions for plumbing this additional pump?

Thanks,

[cal40john]

Originally Posted by SV Escape Plan

I currently have a deep sump with a jabsco diaphram bilge pump rated at 480 gph using a strum box and an inline strainer. I rarely ever have a drop of water inside my boat because of deck stepped rigs so this pump never sees any duty. I also have a large manual whale pump with handle at the helm. I have an area above the sump in the bilge where I would like to mount a big centrifugal style pump with a float switch tied to a high water alarm but am not sure how I would plumb the discharge from this pump. I dont really want to tie it into the discharge of either existing pump because that would require a check valve which is a big no no on bilge pumps in my opinion. I also dont really relish the thought of drilling another hole in my hull. Suggestions for plumbing this additional pump?

Thanks,

Many put the outlet on the transom fairly high up. Otherwise since centrifugal pumps don't have check valves in them if you go to an underwater thru hull you have to put a vented loop above the waterline.

[SV Demeter]

Originally Posted by cal40john

Many put the outlet on the transom fairly high up. Otherwise since centrifugal pumps don't have check valves in them if you go to an underwater thru hull you have to put a vented loop above the waterline.

Pretty much what I was figuring which is why I have not yet done it. Not really looking forward to cutting new holes in my boat.