Bilge pumps

Peter_C · 24 July 2012, 21:31

A long time ago I ran a search for bilge pumps on multiple forums, along with google, and didn't find much related to SIB's. The past couple of days I built a mount and sock so to speak for a small 500gph Whale Pump. The floor clearance is tight, and the auto bilge switch I am afraid will slam into the floor. The pump will stay where it is, but I am thinking of putting the bilge pump switch onto the center keel. I have an on/off/auto bilge pump switch.

Also instead of putting a hole in the floor, I am considering putting the outlet tube from the pump thru the transom in place of one of the scuppers since they don't do anything but leak, and yes I have the plugs.

Has anyone done something similar with a SIB?

Before anyone asks why I would do such a stupid thing, the reason is because under the deck can hold 5 gallons of water that weighs over 40 lbs. When trying to drag it back up the beach to the trailer it is too heavy, so every pound lost is important. Look at my avatar for reference. The rear drains suck!

jyasaki · 25 July 2012, 04:56

Outlet below the waterline? I don't think that'll work. The pump does not act as a one way valve. It'll probably pump out OK, but will allow water back in when off.

You can run an outlet hose out and up; that should work. OTOH, you're going to need to get the wires up to the battery anyway, which I assume means a hole through the floor anyway?

jky

Chris · 25 July 2012, 06:34

Why would you need a bilge pump in a sib ?

Peter_C · 25 July 2012, 07:03

Quote:

Originally Posted by Chris

Why would you need a bilge pump in a sib ?

See my quote below from my first post.

Quote:

Originally Posted by Peter_C

Before anyone asks why I would do such a stupid thing, the reason is because under the deck can hold 5 gallons of water that weighs over 40 lbs. When trying to drag it back up the beach to the trailer it is too heavy, so every pound lost is important. Look at my avatar for reference. The rear drains suck!

Quote:

Originally Posted by jyasaki

Outlet below the waterline? I don't think that'll work. The pump does not act as a one way valve. It'll probably pump out OK, but will allow water back in when off.

You can run an outlet hose out and up; that should work. OTOH, you're going to need to get the wires up to the battery anyway, which I assume means a hole through the floor anyway?

jky

I was thinking the outlet would run up just higher than the transom before it dumps. Wasn't planning on a check valve. That little bit of water can drain back. The wires could easily be run right behind the rear deck mounting plate on the transom, by running a router for about 2 inches across the transom vertically (Maybe 1/4" deep and a 1/4" wide). See my photo for the aluminum piece on the transom I am talking about running the wires behind. Another reason for having everything not run thru the rear floor decking is then the rear deck can be quickly removed without having to disconnect or cut anything. Plus it would be two less holes in the deck.

jyasaki · 26 July 2012, 16:19

Holes in the deck aren't a big deal; I would think a 1" bore wouldn't compromise much. But the disconnecting part is a good call.

I wouldn't bother trying to hide the wires; if the Whale is a "normal" bilge pump, you'll likely be replacing it in a couple/few years anyway.

jky

captnjack · 26 July 2012, 17:09

I'd put a mini elephant trunk on the little one way floor valve. As you drag it up the beach the subfloor area will drain (faster than the pump probably). Since the drain is centered, pull up the trunk underway so it doesn't hit the prop.

Peter_C · 27 July 2012, 08:51

Quote:

Originally Posted by captnjack

I'd put a mini elephant trunk on the little one way floor valve. As you drag it up the beach the subfloor area will drain (faster than the pump probably). Since the drain is centered, pull up the trunk underway so it doesn't hit the prop.

There is a larger 3" elephant trunk on the starboard side (See left side of photo), that I just put in. Happy to say it is so far not leaking either. It is designed to drain the deck of the boat though, and the part I want drained is below that level.

I want it drained before we ever try to lift the bow of the boat. Last time it took a wave over the stern and it was hard to get the wheels back under it. The true solution is simply to get a bilge pump working. It is light and functional.

At this point I am pretty well set on putting the drain hose out thru the port side scupper hole, and running it to the top of the transom before draining. Just need to figure out how to make a 3/4" fitting, fit into an 1 1/4" hole?? With the bilge pump wires and tubing not connected to the aft deck, I can tear the boat down and reassemble it fairly quickly. If the pump ever needs replacement it would be a fairly simple job.

BumbleAbout · 27 July 2012, 09:34

On our Futura we had a hole drilled through the aluminium deck centred about an inch to the right of where your tape measure is and a standard (Rule from memory) bilge pump just fitted inside vertically (gently pushed down against the fabric with bungee cord attached to the deck).

This worked very well to empty rain water out when towing/ in a harbour well inside the speed limited area and so unable to plane/ when recovering to reduce the massive extra weight under the deck!

Peter_C · 29 July 2012, 08:22

Thanks BumbleAbout for understanding where I am coming from. Not sure I understand how you used bungee cord to hold the pump down? I originally bought a Rule 500 (Anyone in the USA want to buy it?), but didn't like how close it was from the bottom floor to the deck. So I purchased the Whale Pump that is much lower in height.

I had to put the boat back together today in order to use it. No way do I want anything attached to the deck that doesn't unclip without tools. So nothing can pass thru the deck.

After taking a wave over the stern parked on the beach I really wished I had completed the bilge project. The elephant trunk worked to drain some of it once I got it off the beach, and back underway. It left gallons of water under the deck that drained after putting it back on the trailer which it got drug up onto, due to surge. Might try to work on that project for a little while tomorrow.

Also almost lost my vehicle into the Pacific ocean today, like in the youtube video's. My gal wanted to drop the trailer in the water. So both gals head over to work the trailer into the water. They were struggling, but I left them alone to figure it out. When the wave washed over the stern, I quickly got the boat off the beach, and sat offshore watching them struggle, but again letting them figure it out, as they are both smart but stubborn, and sometimes learning comes the hard way. One of the Coastie's then feeling bad offered to help. He jumped in the drivers seat, and with a few directions how to drive a Prius, backed the boat trailer like a pro into the water. Then he stepped out of the vehicle with the backup lights still on which meant it was still in reverse

I was yelling it was still in reverse, but it took about 20 seconds before the park button was finally pushed

So how close was I to loosing my car? When we got home, I had my gal get in the car and put it in reverse and set the parking brake in our driveway. The car rolled backwards. Try as she might she couldn't set the brake hard enough to keep it from rolling while in reverse. Toyota in their infinite wisdom used drum brakes which don't hold in reverse very well, ever

The only saving reason was the Coastie was a BIG guy and pushed the parking brake hard, thank goodness.

Cheers to the Coastie's for being so nice and helpful

Just glad nothing happened, but it scared the crap out of me.

falcon0310 · 29 July 2012, 10:54

put non return valve in and you be fine

Peter_C · 29 July 2012, 18:25

Quote:

Originally Posted by falcon0310

put non return valve in and you be fine

Why would I need one? The bilge outlet tube will have less than 40 cm of head height (Outlet at top of transom). Back flushing that little amount of water might help to keep the screen clear.

Never had check valves on my boats before, but have heard of failures when utilizing check valves. Seems much of it has to do with head height and drain back.

Peter_C · 29 October 2012, 20:00

Here is the latest, although it has been tested with success now. Since I couldn't find hardly anything on the subject I will put this out there as a resource for others. I was worried about the Water Witch smacking the bottom of the floor, so I made it adjustable and mounted it to the center tube with Velcro. So far it is staying in place, and works just fine. Most of the time I just flip the pump to manual on right before putting it back on the trailer or for beach recovery.

The transom got routed out a little bit so the wires could pass thru without having to disconnect anything for floor removal.

Since the water has to exit the boat and I didn't need two of the lower scupper plugs I pulled one out, took it to Home Depot with a caliper in hand and within 2 minutes had a solution. Total cost less than $5. A reducer coupler, a bunch of elbows and back home I went to work on it. I already had the pipe and tubing. I just had to enlarge the scupper hole a little (Started with a power rasp, and switched to a hand rasp) to make room for the coupler which was glued in with 5200. The elbow and pipe didn't want to clear the floor so a little work with the heat gun shaped everything to fit together.

It is a very busy transom, but somehow there is room for everything. I tip the depth sounder up to clear the tie downs as seen. The aluminum bar in the middle is a transom saver I picked up from Craigslist for a smokin' deal, then modified it to work with my setup. The 8ft antenna is on the left, and the aluminum pole on the right is for my dive flag and eventually a 360 degree anchor light. It slides into a fishing pole mount that came with the boat, which makes taking the flag down easy. The blue deal is my 3" elephant trunk that mounts just above deck. Of course the launching wheel legs and brackets can be seen too.

maxitope · 29 October 2012, 21:38

i have just got a seaflo 600gph cartridge airator bilge pump for my honwave, but am having problem geting it to prime up the long bottom intake ,has any one fitted one of the same and if so please give me some advice.

Peter_C · 29 October 2012, 21:53

maxitope, I am assuming you mean an aerator pump that has the long threaded tube on the bottom? If so it will not prime unless the pump itself is submerged. I have two of those style pumps made by Attwood, and they require the impeller to have water flowing around it in order to start the flow. Once flowing they can produce a little bit of head lift, but that is not the right pump for the job. Aerator pumps are designed to be submerged like 95% of the bilge pumps on the market.

I looked into a vane type pump, that will suck water up from below, but they draw a lot of amperage, and are expensive.

So far the Whale Pump is working for me and it is a 500 gph. I couldn't find anything else that would fit under my decking.

maxitope · 29 October 2012, 22:42

hi peter c thanks for that ,just been on to firm i got it off and he is sending out a replacement as i thought it was faulty

Peter_C · 29 October 2012, 22:59

Huh? Have you applied power to it and submersed it in a bucket? They are a very simple design and there isn't much to go wrong. If it makes noise it is probably working.

As I said, it is the wrong kind of pump for what you are trying to do.

Locozodiac · 29 October 2012, 23:44

Bilge pump is useless on a sib, you will need a battery too. Just trottle enough engine for sib to performa a wheely with water valve opened and you are done, probably will take it's time, can drink some cold beers while releasing water....

Happy Boating

ian parkes · 29 October 2012, 23:55

just get a hand bilge pump and shove the hose under the floor .Strap it to the transom if you want it fixed in place
an electric pump in a sib is daft and a hand pump will pump faster than a small electric and be reliable

Peter_C · 30 October 2012, 00:13

Quote:

Originally Posted by Peter_C

Before anyone asks why I would do such a stupid thing, the reason is because under the deck can hold 5 gallons of water that weighs over 40 lbs. When trying to drag it back up the beach to the trailer it is too heavy, so every pound lost is important. Look at my avatar for reference. The rear drains suck!

Y'all need to read my reasons before commenting that SIB's don't need pumps and a hand pump is good enough.

My boat has a very nice Hawker Odyssey PC925 AGM battery. Electrical power is not a problem. It also powers my VHF and more importantly my chartplotter/sounder/GPS for finding dive sites, along with providing electrical start for the engine. Next you are going to tell me I don't need a DSC equipped VHF radio, nor a depth finder

First of all I am mostly worried about beach landing and taking a wave over the stern (Been there, done that). There is no driving around and drinking a beer between scuba dives either.

Ian, if you believe a hand pump is more powerful than a 500 gph pump, I would inform you that you are gravely mistaken. I own a nice stainless steel shafted hand pump and it won't even come close to what the Whale Pump can continually kick out. In that same note my electric pump works completely automatically leaving me and my crew to recover the boat back onto the beach, while you are still pumping with your hand pump, as another wave breaks over the stern. A hand pump when you don't have hands available is daft

No wonder I never want to post up my lame work, as someone is always critical when they either couldn't do the work themselves, or think they have a better way.

ian parkes · 30 October 2012, 00:47

try it peter you can shift about 50L a min with a pull up down simple hand pump , for a few gallons it is quicker . I think 500gph works out to 30L a min .

Anyway what i meant was not to split hairs with amounts and how fast you can pump but simplicity and reliablility of actually beaing able to pump when you need to.

I know what you mean by the wave over the stern if you get a surf landing a bit wrong with a slow crew . That wave usually brings with it a load of sand or pebbles and weed and an electric pump inacessible under the floor fails too easily . plus a wave in small rib has a battery under water and the fuel tank floating . plus that floor is giving the pump an extreme trampline ride .

I helped some guys last year on the beach after they moored their speedboat by the sternpost in small surf , it filled up and the pump lasted about 2 mins then it sank in 3 ft of water