Mystery water in bilge

[bgary]

For some time, I've had mystery water in my bilge.

Some of it ended up being rainwater, and I've solved all the places where it was coming in.

Now, while sitting at the dock, a dry bilge stays dry.

But underway.... not so much. Motoring, I get about a gallon an hour of sea-water in the bilge. Sailing, sometimes more.

It bugs me.

I've done sort of the mental checklist, and it looks like this
-- Keel bolts? No, I suspect they'd be leaking at rest, too, and they're not
-- thru-hulls in head? No, no sign of water around the thru-hulls or hoses
-- thru-hulls in galley? No, again, no sign of water around the thru-hulls or hoses
-- engine plumbing? No sign that any pumps, hoses or fittings are leaking
-- rudder gland? dripless? Nope. Nothing significant (maybe a few drops of cast-off from the dripless, but no "drip")
-- other holes in the boat? O_O

...so, what's that leave? the #32-III has 6 thru-hulls in the "counter" under the transom. One for each scupper in the aft corners of the cockpit, one for the electric-bilge-pump discharge, one for the manual bilge-pump discharge, one for the propane-locker vent, and one for exhaust.

So the checklist goes
-- exhaust? No, sign of water around the thru-hull or anywhere along the hose run
-- scuppers? No sign of water around the thru-hull, and if water was coming in it would show up in the cockpit, not the bilge
-- propane tank? No sign of water around the thru-hull, and, again, if it was coming in it would show up in the tank locker, not the bilge

...so that leaves the pump discharges. Electric bilge-pump hose has a vent loop. Manual bilge-pump hose does not.

So, I'm wondering... is it possible that when the boat is underway and/or heeled, the water under the counter rises to the point where it can make its way into the manual bilge-pump discharge, through the hose, backwards through the manual bilge pump, and down into the bilge?

It would explain why it is *only* happening under way. I think.

Anyone else have this problem?
Good ideas for a fix? or even a test to see if that's really what's happening?
and...what else am I missing?

Bruce

 

[toddster]

Was the prop-shaft stuffing box on your list?

After a long process of fixing obvious deck leaks, I've been having some similar issues. Current leading - but untested - theory is a short inaccessible hose that leads from the aft scupper to the transom may be leaking. But another issue on my boat is that there are inaccessible sections of the bilge that only drain to the main bilge when the boat is heeled over. So water that could have got in there days or weeks ago suddenly dumps into the bilge after a spirited sail.

 

[Pat O'Connell]

Scupper Leak

Hi Bruce
Sorry to read that the leak tough to find. Had that prob when boat was new. It was the scupper that would submerge when under way. Very hard to find. New scupper fixed it. (4) of us stood on the bow and the stern and the cracked stern scupper was above the water line. I would temporarily plug the scuppers and see if the leak goes away. See if you can submerge the scuppers for inspection by weighting the stern with crew.
Good Luck!
Pat
1981 E28+ Universal 5411

 

[bgary]

Was the prop-shaft stuffing box on your list?

Yes, but crossed off (I think). Makana has a dripless... there's no sign of water anywhere near it, except a few scattered drops of "cast-off" from the part that spins.

And, yeah, I too have water that comes out from under hidden areas of the TAFG when under sail. But this most recent weekend I motored nearly the whole way from Everett to Port Ludlow in a dead-flat calm. flat water, no heel... and had water showing up in the bilge. That's what makes me think that something is going on in the stern...

 

[bgary]

See if you can submerge the scuppers for inspection by weighting the stern with crew

Good idea! I had also thought about pointing a hose into the bilge-pump discharges, to see if it is even possible for water to make its way backwards through the pump to the bilge.

"in theory", the valves on a manual bilge pump should act like a check-valve (only allow the water to move one direction).

Not sure if there's still a check-valve on the electric bilge-pump hose. We'll see....

 

[Pat O'Connell]

Scupper Leak

Hi Bruce
Just recalled another devil in the details. Our boat has a plywood insert at the transom so the thru hull can not be observed where it enters the hull. :<{(((
Best Regards
Pat
1981 E28+ Universal 5411

 

[fool]

Yes, but crossed off (I think). Makana has a dripless... there's no sign of water anywhere near it, except a few scattered drops of "cast-off" from the part that spins.

Please reconsider checking off the dripless, which may need a simple adjustment. Mine did not drip at all during idle or rev'd at idle, nor in reverse, nor rev'd in reverse, but did in forward. Just a few drips when under power in forward at idle, but then it turned into a bath at higher RPM's. Nothing wrong with the PSS, just needed the rubber re-adjusted against the carbon (the part that spins).

Took about a week to figure out when it should have only taken five minutes. Truth be told I thought it was the head that was leaking and was distracted by trying to figure out how to test that theory.

Oh look over there, another shiny thingy...

 

[bradh]

Ok - this one is from experience.... is it your ice chest? I know that sounds crazy, but mine drains into my bilge. Go out for a sail, drop some ice in the chest and there you have it.

A humility story: when I first bought my boat, I noticed after some sails, but not all, I would have water in my bilge(!). But it was clean... and then when I touched before turning the pump on one time..... cold. Duh.

 

[Ken Haneline]

Bruce: I just had to disconnect the hot water tank from the water exhaust system. The prior owner had disconnected the water system from the tank, but not the exhaust water that was used to heat the tank. I found the leak by going underneath while the motor was running. I simply looped the exhaust water hose in a loop back into the exhaust system. Dry bilge now. Good luck, Ken

 

[Tom Metzger]

On Xanthus I added a syphon break in the bilge pump hose at the top of the transom which eliminated the problem of water backing up through the bilge pump when under power.

I think it would have worked just as well if I had put it in a more accessible spot. I'm not at all sure I could get to it now that I am 20 years longer of tooth.

I don't like the idea of a check valve in the bilge pump plumbing.

 

[bgary]

Thanks for all the great ideas.

With regard to the dripless, I should have been more clear about my recent "investigation"... on Saturday I was motoring across the Sound in dead-flat, deserted water, went below to grab sunglasses and checked the bilge out of habit while I was there. Found about 4" of water, where there had been none when I left the dock a couple of hours earlier.

Pumped it out and then - popping my head back up periodically to be sure there was no traffic approaching - spent the next 10 minutes going thru the boat, checking all the thru-hulls, all the engine plumbing, etc, all while the boat was motoring at 2200rpm (6-1/2 knots) in flat water.

No signs of water coming in at or near any of the head or galley thru-hulls. No signs of water coming out of any hoses. No signs of water coming out of raw-water plumbing, fresh-water plumbing, pumps, water heater, exhaust riser, etc. No signs of water near the transducers. No sign of water coming in near rudder gland or dripless. No sign of water coming in around any of the discharge fittings under the transom.

That's why my theory is currently centered on bilge-pump hoses.... because I don't see water coming *out* of any hoses or fittings and draining into the bilge, it must be going "through" hoses straight into the bilge. And because it only happens underway, and those are the only paths that are above-water when docked, but could be immersed while under way.

Can't think of what else it could be. Will do some testing on Saturday.

(edited to add) My icebox doesn't drain to the bilge, it is plumbed through the foot-pump to the sink-drain thru-hull...

 

[bolbmw]

I would be suspicious of any other hidden areas where water may collect and move when underway, even a few extra degrees of fore/aft/side-to-side movement may cause that water to move. I've found areas on my boat which don't drain unless the boat is moving around. They're also totally inaccessible without destroying the floor. Hooray

 

[bgary]

From another thread...

What did you get for discovery on your bilge leak?

Short answer... still investigating.

I did some testing on Sunday. pulled a section of the bilge-pump hose up to form a loop well above the level of the below-transom thru-hulls, and.... still had water coming into the bilge while motoring around. So... it isn't that.

So... starting to give a stink-eye to the dripless. Since there is no evidence that the water is coming in through a thru-hull or hose, there isn't a lot else to look at.

One interesting (?) thing happened Sunday morning.... I went to back out of the slip and found the shifter-lever didn't do anything. So I shut down and found that the fasteners on the shift-cable clamp at the transmission had rattled loose. Got them tightened, added them to my list of things to periodically check.... but along the way, while leaning across the shaft trying to figure out how to get wrenches on both sides of the fastener from the wrong side of the boat... I nudged the dripless bellows and was surprised at how much water came in. And, interestingly, the water went straight into the "real" bilge (through a cut-out in the TAFG under the shaft log), so... that might explain why I'm not seeing any evidence of water flow through the normal paths... it just shows up from somewhere under the TAFG.

Anyway, I called PYI on Monday, asked if there was maintenance or adjustment that might be needed, they said yes... the bellows can lose "springiness" and that can result in insufficient pressure holding the two carbon plates together He said that "every year or two" it is a good idea to remove the setscrews from the stainless ring, push the ring 1/4-1/2" toward the bellows, and then secure it in place with new set-screws (he said the ones they use are single-use cup-points that crush when tightened, and said he'd send me a new set in the mail).

So, when those arrive I'll make the adjustment and see if that makes a difference. If nothing else, it's good to be aware of the fact that the dripless might need annual inspection to make sure the bellows are pressing the parts together with enough "ooomph".

ObNote, they also say the bellows should be replaced every 6 years, so that's on the list for my next haul-out, probably spring 2018. I'll add the upgrade for a vent-tube at that time, too.

 

[Kenneth K]

.....they also say the bellows should be replaced every 6 years, so that's on the list for my next haul-out, probably spring 2018. I'll add the upgrade for a vent-tube at that time, too.

I've always been curious: What does the vent tube do? Mine doesn't have one.

 

[Kenneth K]

Also, do you remember Christian's blog about adding the rudder-post grease fitting (zerk) and re-greasing the rudder shaft? I seem to remember him saying he had a steady inflow of water through the rudder packing gland (only when the boat "squatted" down" while motoring) until he added more grease. Have you checked the zerk fitting?

 

[bgary]

I've always been curious: What does the vent tube do? Mine doesn't have one.

Simply lets air out of the bellows so that you don't have to "burp" it when the boat goes into the water.

The dripless design depends (I'm told) on having the bellows full of water to keep the plates cool

 

[bgary]

...a steady inflow of water through the rudder packing gland (only when the boat "squatted" down" while motoring)...

I haven't checked the zerk. But I did spend time with a flashlight looking all around the rudder gland (and aft thru-hulls) while motoring en route to Ludlow last weekend, and didn't see any signs of water.

Of course, I didn't see any around the dripless, either, so... it remains a mystery.

 

[Alan Gomes]

Simply lets air out of the bellows so that you don't have to "burp" it when the boat goes into the water.

The dripless design depends (I'm told) on having the bellows full of water to keep the plates cool

Didn't MaineSail mention somewhere that water can come up out of that vent when powering in reverse? I recall that he set up some kind of a hose system to that vent so that the water wouldn't wind up in the bilge. It may have been a thread on the SBO site, or possibly on his own. At any rate, might that be a source of *some* of your water?

 

[bgary]

water can come up out of that vent when powering in reverse

Mine doesn't have the vent, so.. no.

But it does raise an interesting question... I've only checked for water ingress while motoring forward. I wonder if water could be coming through when motoring in reverse....

Hmmm....

 

[Tom Metzger]

I did some testing on Sunday. pulled a section of the bilge-pump hose up to form a loop well above the level of the below-transom thru-hulls, and.... still had water coming into the bilge while motoring around. So... it isn't that.

Not trying to beat a dead horse, but on my E-34 the bilge pump hose runs just under the transom cap rail, forms a loop well above the level of the below-transom thru-hulls, and the water siphoned into the bilge when powering because the stern squats down and puts the thru hull below the water. It required a siphon break.

Different boat, likely a different problem.