Bilge pump hose

[Andrew Harvey]

Recently whilst cleaning out the bilge buy filling it with fresh water for a flush, I turned on the electric pump which was pumping well but the level was not going down. All it was doing was recirculating.
A slight tug on the hose assembly revealed the problem as I held the pump and about 6 feet of PVC pipe in my left hand.It seems that the connection between the pipe oand hose is buried under the floor somewhere between the bilge and engine bilge. I ran a new hose directly to the thru hull from the bilge via a check valve but this set up is not working wel as air seems to get in the bilge pump.
Was there some kind of vented loop in the original installation ?
Is there a problem using a check valve?
I don't like having 3 or 4 inches of water in the bilge all of the time.

[Ron Hill]

Andrew: You don't want a check valve in the bilge pump hose.  A vented loop is installed in a line that exists the boat via a underwater thru hull to prevent a "back" siphon.  A bilge pump exit should be above the water line - NEVER below the water line.
 
It's the "nature of the beast" that the water in the hose will flow back into the bilge.  If the bilge pump exit is too high the pump won't have enough "head" to pump the water out.  There might be some slight back flow from a following sea, but easy to sponge out.
What you need to do is install some Gore Drippless Packing - that way you'll have a dry bilge and keep that nasty water out of there.   

[Stu Jackson]

Andrew

On our boat the electric bilge pump hose is directed through the same hose that goes through the manual pump in the cockpit.  I recommend checking the hose routing, because if you've simply run the electric pump to the thru hull, you may have disconnected the manual pump.

[kss1220]

The thru-hull exit for the bilge pump on the Mk1 is actually below the water when the boat is moving. This allows water to re-enter the bilge area unless a check valve (not recommended) or a vented loop is placed near the thru hull above the water line.  In my case I installed a vented loop.  The ideal situation is to install a new thru hull higher than the factory position to eliminate the issue.

[Bob Hallman]

OK, so after three years of no problems I'm having a problem with the bilge pump not pumping when the float operates. The pump will sit there and run and run without moving water. If I bump it a couple of times the thing will empty the bulge. In review the previous messages I'm not exactly sure of the correct solution. My discharge is above the water line at anchor and below when underway and its never been a problem until the past couple of weeks. Thoughts please.

[Ron Hill]

Bob : Sound to me like you have a loose hose clamp on the pump, clogged pump intake or a crack in that hose fitting?   

[Stu Jackson]

or you need to replace the pump.  Sometimes when the impeller gets a bit worn it won't start pumping right away.  For peace of mind, try a new pump, after checking Ron's hints.  Like take the pump off its base and see what the bottom looks like, if you haven't done so already.

[Bob Hallman]

I did lift the pump off the base. The suction screen looked OK and so did what I could see of the impeller. I'll get it a closer look this weekend. I'm thinking with that pump sitting in the water the suction is flooded and it should pump. Stu may be right, the pump might be getting tired. Maybe take a pump along from my local West Marine. Thanks for your opinions!

[Mike and Joanne Stimmler]

Hi Bob, nice to see your name pop up. I think these guys are giving you some pretty good advice. I'm betting on a problem woth the pump itself, since you said " the pump runs but does not pump water, but if you bump it, then it pumps". I think you'd be wise to take a new pump with you next time.

One other possibility is that there a "LEECH" stuck in the pump!!!!   

Kep in touch,
Mike & Joanne

[Hugh17]

As noted by kss1220:"The thru-hull exit for the bilge pump on the Mk1 is actually below the water when the boat is moving. This allows water to re-enter the bilge area unless a check valve (not recommended) or a vented loop is placed near the thru hull above the water line."

Since I purchased my boat I had noticed when going below while under power that the bilge pump indicator light would come on periodically, but couldn't figure out where the water was coming from until the float switch on the bilge pump failed and the bilge filled with water on a recent trip.

After pumping the water out by holding on the manual switch, I checked every through-hull and the drive shaft for a leak. I finally determined that if we had 3 or 4 people in the cockpit, and if the engine was running at a higher RPM the stern would squat low enough in the water for the through-hull exit for the bilge pump to be underwater. And this is where the water was coming from.

Since the float switch was inoperable we tested our theory several times by slowing down enough to keep the bilge through-hull fitting above the water line and no water came back into the bilge. When we sped up enough to submerge the through-hull then water would flow into the bilge coming out of the electric bilge pump.

The problem is that the check valve had obviously failed. As suggested by KSS1220, he installed a vented loop, I assume in the aft lazarette locker. And I agree that the through hull should be installed higher up on the transom. But without a check valve there is still a chance that the bilge pump will continuously cycle as the volume of water in the line flows back into the bilge after the pump cuts off. I already have this problem just with my air conditioning draining into the bilge.

I replaced the float switch at the next stop on my trip and will replace the check valve as soon as I can locate a suitable replacement. Adding a vented loop or raising the exit point on the transom will have to wait a while. 

[Ron Hill]

James : You mentioned the real solution - raise the electric bilge pump exit on the transom !!

Adding more items into a simple hose line could be problematical in the future.  it's your boat!!

A thought

[SPembleton]

I just launched yesterday, got out in Lake Michigan and found a couple of inches of water in cabin when heeling.  Bilge pump was humming and water not getting deeper. Panicked!  Checked all through hull fittings and engine cooling hoses. Nothing looked wrong. Went back to marina into the lift.  After inspection I realized that the screen on bilge pump was totally plugged.  Not actually taking on any water.  Pump was humming, but not pumping. Water in bilge was just normal accumulation over winter.  Looks like more when heeling. Cleaned screen and bilge emptied. After 6 hours still good. Something new to add to spring checklist. Keep reminding myself that every crisis is a learning opportunity.

[KWKloeber]

I just launched yesterday, got out in Lake Michigan and found a couple of inches of water in cabin when heeling.  Bilge pump was humming and water not getting deeper. Panicked!  Checked all through hull fittings and engine cooling hoses. Nothing looked wrong. Went back to marina into the lift.  After inspection I realized that the screen on bilge pump was totally plugged.  Not actually taking on any water.  Pump was humming, but not pumping. Water in bilge was just normal accumulation over winter.  Looks like more when heeling. Cleaned screen and bilge emptied. After 6 hours still good. Something new to add to spring checklist. Keep reminding myself that every crisis is a learning opportunity.

An old salt Canadian sailing instructor once told me -- -when in the midst of an emergency at sea -- STOP sit back, have a BEER.  THEN assess what's going on (troubleshoot) 

He claimed, 9 times out of ten it's something easily discovered and fixed, and unless you take the time to calm down and be able to think it through logically, oftentimes you get yourself into more trouble than the original problem.

I've found that to be very solid advice more than one time that I've found myself beginning to 'panic'.

kk

[Steve McGill]

James, As Ron suggested raise the pump exit.

On Clarity I have 4 exits on the transom.
There are two for the propane locker and two for the bilge. My lowest on the transom is the
whale hand bilge pump, then a propane locker then the electric bilge pump exit. My hand whale pump is located
in the aft locker just above the cockpit sole, no worry about water entering from that. With my current arrangement
the thru hull exit for the electric bilge pump is well above the water level regardless of speed.

It may have come from the factory that way, but my guess is that if there was a previous owner they put it on the
lowest thru hull thinking that less water may return to the bilge after the pump shut off.

Always something...........................

Steve

[patrice]

Hi,

One suggestion that I read here once, and still on my to do list, is to make a loop Under the kitcken cabinet that will go higher than the thruhull of the bilge pump.
So won't have much water comming back into bilge after pumping.
And don't need the check valve