How can I stop the air locking of my bilge?

[LogicAl2008]

I have found, time and time again, that I can turn on my bilge pump and nothing comes out, even though there's plenty of water there to pump out.

When I ...

1. disconnect the hose,
2. run the pump for a second (to ensure it is working - it starts regurgitating water),
3. blow into the disconnected end of the hose to clear any blockages, and
4. re-connect the hose to the bilge pump.

... turning on the bilge, again, I now see water pumping out of the boat.

This is obviously an air-lock situation. But, how do I prevent it?

I am very concerned about leaving the boat uncovered overnight and getting a huge downpour that requires the pump to automatically turn on, but it can never get the water out due to the air-lock.

 

[scooper77515]

It could be that the pump sits too high or the sensor sits too low.

What kind of boat is it?

My 97 challenger did this. It would rain a bit, the bilge would automatically come on, it would suck all but the last inch or two of water out, but the sensor still "felt" water so it stayed on. In the morning, boat is full of water and battery is dead.

I just bent the sensor up a little bit so it would not "feel" dry before the bottom of the bilge pump was out of the water.

I still have an inch of water in the bilge, but the pump turns off before it starts to suck air.

 

[LogicAl2008]

This is a 2008 Seadoo 180 Challenger SE with just over 30 hours on it.

The bilge is not coming on automatically, it's not getting filled with that much water, yet. I know there's a lot of water to blow out when I'm done hosing her down and can see a high water hold in the floor/wakeboard storage compartment.

When I turn on the bilge, nothing comes out. When I disconnect the outlet hose and run the pump, water is picked up by the pump. I lean in and blow thru the disconnected outlet hose to make sure there's not blockages. It feels like I clear something, but nothing ever shoots out of the other end.

I then re-connect the hose and re-engage the bilge ... and water starts blowing out the side bilge hole, as it should've w/o my intervention.

 

[scooper77515]

Sounds like something blocking it. Pull the pump out. Most of them just snap out, and see what is under it.

I found the neck-ring of an old beer bottle stuck in mine that eventually burned it up. Pulled it out, and the chunk of glass, and put in a new pump with a little more gph, and it works fine now.

 

[LogicAl2008]

Scooper: I appreciate your being "on the case" to try to help, but are you reading what I write/detail?

When I take the outlet hose off the pump, water is pumped by the bilge.

There is an air lock (like vapor lock) in the outlet line and I need to know what causes an air lock and how to remedy it.

 

[scooper77515]

Honestly, I don't know what an "air lock" is.

The pump system is pretty simple. That is why I am making suggestions that are basic to the pump system.

Verify lines are clear, verify power to pump, and pump works, and switch is working appropriately.

If there is enough water to cover the pump blades and fill the tube out, and the pump is actually "working", I don't see how any amount of air in the line or cavitation, or whatever would cause it to stop pushing water out.

My personal opinion, however poor it might be, is that the pump itself (or the switch) is faulty, and I would spend the $30 for a new one and snap it in. I think you would be done with it after that.

 

[LogicAl2008]

An air lock, like vapor lock, is an air pocket that holds what is trying to push past it back.

 

[wazooo]

The first time I turned on the pump switch on my 07 Challenger the pump hummed but no water came out. But after 20-30 seconds it started pumping water. So maybe you just have to wait a few seconds.

 

[LogicAl2008]

I'll have to try that.

What I did find is that if I just grab the outlet hose and wiggle it firmly, the pump starts pumping water out of the bilge. So, no more disconnect/blow/reconnect steps, it seems.

 

[rexsteiner]

Doesn't it suck when people post advise to something completly irrelavent to the problem your having?lol

My bilge does the same thing and so does my pump for my fat sacs. As soon as I shake the hose up and down it starts pumping. With the fat sac pump its no biggie. But who wants to crawl into an engine compartment everytime to use the bilge? If you find a solution to get the air lock out of the pump let us all no. Ill see if I can figure somthing out too this weekend

 

[LogicAl2008]

Do I even dare ask what is a "fat sac"? :ack:

 

[rexsteiner]

Their ballast bags for weight. You fill them up w water. I have two that hold 400 to 500lbs each. But they use an aerator style pump too just bigger. Its 1100 gph I think.

 

[RFoster130]

If it is an 08 and probably under warranty why not just let the dealer fix it.

 

[phough5757]

I think its routing.

Try keeping the discharge hose low in the bilge so there is water on both
sides of the impeller in the pump. I don't know how long the discharge hose
is but it could take a couple of seconds to start moving the water.
Good lock!

 

[LogicAl2008]

Spoke to a SeaDoo Tech at the local service center for SeaDoo.
He said it's not uncommon for the 180 Challenger to get air-locks on the bilge.

He told me to try to ensure the outlet hose has a smooth, climbing transition with no drops along the way. Keep it always going up, up, up. If you get a bend, you get a p-trap like situation in a drain that then traps air.

Off to work on that line now. More as I know how things worked out.

UPDATE1: I cut out almost 12" of excess bilge hose. I took the starboard side cooler bin (and seat support) out to have better access to the bilge hose. I then cut out the excess hose AFTER I removed the "loop" in the hose near the outlet. If air is getting trapped in sagging hose sections, it will get trapped at the loop, too. We shall see what happens in the days ahead.

UPDATE2: Just went out on the boat today. Tried the bilge with the manual switch and it grabbed water and pumped it out with just a little hesitation at the very beginning. This is the best it's behaved without me touching the hose since we got the boat. So, getting all that slack out of the bilge hose seems to have solve this.