Is it possible that water comes in through bilge pump water outlet hole?

[seilings]

So we just had a great weekend at Harrison lake,BC. We did first time tubing. Lots of fun and most of the time when I pull the tub, the bow was up and made big wake behind for the tubing fun, and I believe the hole was under the water.
And we stop in the middle of the water to swim for quit a while like one hour, everything normal.
Until retrieving the boat and pulled it up to the top of the ramp, and a nice guy told me my bilge pump was on. ( I guess that is the only time when it was on because of the uphill position of the boat).
Anyway when I got home, I did found lots of water in the bilge. And I use a manual pump to pump out about 10 litters of waters.

Any ideas how the waters come in? Bellows leaking?

I guess need to launch it next weekend to do a test.

 

[500dollar744ti]

It could be one of many things allowing water to enter but the answer to your question is yes.

The outlet for the bilge pump can and will allow water to fill the bilge if it does not have a riser in it. To fix that, all you have to do is elevate part of the pipe way above the water line before it exits the boat. That way the water can't make it over the 'hump' you have created even if the bilge outlet is below the water line.

It would look something like this and all the bilge pumps in your boat should have a riser loop. You don't want to made the riser too high or it will create resistance when the pump is trying to work. It just needs to be high enough so that the water will not come back into the bilge.

I always do is this way because I don't trust check valves and one-way valves or whatever with something as important as a bilge pump.

 

[Scott Danforth]

you should be pulling the plug as soon as the boat is out of water (when you are strapping down the transom). not sure about the laws in BC, however I know in many states its a requirement, many ramps even require you to rinse off the boat and trailer and rinse out the bilge to prevent inadvertent transport of invasive species.

 

[seilings]

It could be one of many things allowing water to enter but the answer to your question is yes.

The outlet for the bilge pump can and will allow water to fill the bilge if it does not have a riser in it. To fix that, all you have to do is elevate part of the pipe way above the water line before it exits the boat. That way the water can't make it over the 'hump' you have created even if the bilge outlet is below the water line.

It would look something like this and all the bilge pumps in your boat should have a riser loop. You don't want to made the riser too high or it will create resistance when the pump is trying to work. It just needs to be high enough so that the water will not come back into the bilge.

I always do is this way because I don't trust check valves and one-way valves or whatever with something as important as a bilge pump.

Thanks for the diagram. Last time I checked, my bilge pump pipe does not have a riser loop.
Although I thought the boat manufacturer should already thought about this, and everything I got should be fine.

 

[seilings]

you should be pulling the plug as soon as the boat is out of water (when you are strapping down the transom). not sure about the laws in BC, however I know in many states its a requirement, many ramps even require you to rinse off the boat and trailer and rinse out the bilge to prevent inadvertent transport of invasive species.

Most of boat ramps in Vancouver BC don't have water line for boaters to rinse off the boat. I guess they don't have such regulation.
You are right, I should pull out the bilge plug after retrieving the boat, just for draining water while driving home.

 

[airshot]

Had that same problem last year and came to realize that water was backing in thru bilge outlet. Did as suggested and added a riser loop in outlet hose and no problems since. Same theory for the vent tube for your gas tank, some boats have water in their fuel by water backing thru the vent, add a riser loop and keep water from entering fuel tank.

 

[redneck joe]

buddy bought an 06 Chapparell deck boat last year, same bilge pump issue - plus a rip in the line.