Bilge Water

[richie30]

Was sailing Pazzo last week, on Lake Huron, with a following sea (3-4 feet) I was trying to make time, so was also running the diesel. Was going about 7-7.5 knots. I went down below, and checked the bilge ( as we were 7 miles off shore, and lots of fresh water! I think it may have been syphoning back in from the bilge pump??
I carried several buckets out, and was running the pump as well. The engine was running fine, no apparent leaks, no abnormal temperature reading. I shut the engine down, dropped the speed back to 6-6.5 knots, and the water stopped flowing in.

Any thoughts or others with a similar concern?

Thanks

Rich

[stu jackson c34]

Same concern for the last 11 years. Haven't done anything about it. Solutions? Vented loop, new hose, more intelligent system than a Rule pump and a flipper float switch.

But it works, pumps out what gets in from running downwind, and keeps the drip, drip, drips out of the boat. No check valves for me on a bilge pump line.

[ProfDruhot]

Stu,

Are you saying that you would not suggest having a check valve on a bilge pump?



Same concern for the last 11 years. Haven't done anything about it. Solutions? Vented loop, new hose, more intelligent system than a Rule pump and a flipper float switch.

But it works, pumps out what gets in from running downwind, and keeps the drip, drip, drips out of the boat. No check valves for me on a bilge pump line.

[deising]

Glenn,

In an ideal world, check valves could be good. On a boat bilge - bad idea.

I personally know of a boat where the check valves stuck closed and all the bilge pump did was run with no effect. Even when they open fully, check valves often reduce the flowrate through the hose. Most boats have marginal bilge pumping capability as it is.

[stu jackson c34]

Check valves in bilge pump lines is a horrible idea, a disaster waiting to happen!

[benethridge]

How about this:

Double-Y the bilge pump lines with one line having the check valve and the other not, like so:

_____Check Valve______
/ \
BP______/ \_____________Above WL Thru-hull
|\ /
| \_____________________/
|
|
Two ball valves or a single 3-way ball valve here. Shut off one or the other line out.

That way, when you have no large following sea, you can run the pump through the non-check-valve line, and on the unusual days when you have the large following sea, you can check the line, and thus stop any backflow.

Do you really think that's what caused it? I mean, was the boat heeling over such that the thru-hull spent several seconds underwater? or was it just splashing onto the thru-hull now and then?

[benethridge]

Sorry, my drawing is not coming out, due to HTML idiosyncrasies.

[mutualfun]

Rich:

I am out on a 2 week vacation atm, and have the same issue in following sea's. What I have come to conclude is that it is coming from my rudder post packing. Reason I think that is, The bilge is in sections. I have plugged the weep holes with putty so it helps isolate where the water is coming from. I am getting it in the rear compartment which is isolated from the pump.

This tells me it is from the rudder post. What I need to do is to take a look once in following sea's again to confirm this. I installed a new bearing system last spring but may need to revisit the packing gland and have a look. I am sure others will have input to this also.


Randy

[dwarburton]

Randy,
What year is your Catalina? The last time I was in the locker of my MKII, I thought the rudder post exited the hull above the water line. Just curious, no leaks this week.

Regarding the bilge pump, I got tired of the entire discharge hose emptying itself back into the bilge after the pump ran, so what I did was install a loop in the discharge line under the sink. I used elbow fittings to make the loop tight enough to fit.

The hose now makes a right angle turn vertically next to the sink, does a u-turn just below the counter, which is above the water line and the bilge discharge. Then it goes down, again, makes a right angle turn and continues on its way.

This means only the water between the loop and the pump drains back into the bilge. This would also prevent the back flow in a following sea.

You do not need a vented loop because the bilge pump will not pump a high enough volume of water with the bilge nearly empty to fill the hose completely and cause it to siphon. there is enough air gap in the partially filled hose to break the vacuum.

[mutualfun]

Ours is a 1990, My thought process is what happens in a following sea is the force of the water up and under the rear of the boat pushes the water up into the packing gland area.

I redid the top bearing and made a nylon bearing support so the rubber shaft has no side to side movement now. Which I had suspected before I made the improvements to the top bearing and the rudder shaft bearing tube.

What I need to do it pull the cushions out of the aft cabin and have a look when in following seas. Just a process of narrowing things down. I am one that like a dry bilge. I have a drip less packing gland so it is not coming from there from what I can see. As it is only in following seas that this happens.

Randy