Back Flooding thru bilge pump??

[Loren Beach]

After a hard sail a couple nights ago, I found about a half inch of water wandering around the bilge sections. We had been sailing a couple of hours with the full main and 135, in about 15 kts of breeze. Lots of time at 8 knots on the speed guage, and the stern wave up a foot on the transome for much of the evening.


If short crewed, I would have reefed. With 6 racing buddies, we had someone to play the traveler *and* someone to play the mainsheet... Even had people parking their butts on the weather rail, like we were serious!

Great Fun!

About that water...
Natually the loose water got up into the shelf by the nav station on starboard tack... This tendeth to vexeth the captain mightily...


So I sponged it all out, muttering vile words. Where did it find a way in?

Admission: I may have made a big error when I replaced one of the original Par bilge pumps with a Rule pump several years ago. Those $pendy Par diaphram pumps work by a check valve system and do not allow back-flow. The Rule centrif. pumps have a much higher GPH rating, but can let water siphon back in...
The exit hose inside the transome is looped up a couple of feet (!) above the DWL, and is normally empty and should never support any siphon action.

Or, did all our heeling and general movement shake loose some water lurking in the bilge hose runs (2 electric, 1 manual)? We did shake up the boat a lot, what with lots of power boat wakes, and short wind chop.
We did not, OTOH, take any wave tops over the deck, it was not that choppy...
As a trial, I am thinking of removing the Rule pump (it has a tendancy to air lock once in a while during testing), anyway. I could plug the hole in the transome and use the remaining Par diaphram pump to de-water the bilge when needed. (Which is mostly never, we keep it sponged dry.)

Any thoughts on this problem?

Loren in Portland, OR
Olson 34 #8

 

[Geoff Johnson]

Loren, I don't know how the Olson is constructed but on my 32-3 I have discovered that there is an area lower than the visible bilge where water collects, presumably draining from the visible bilge (possibly up to a gallon). So even if you think the bilge is dry, there is still water to slosh around, although with the deep bilges on my boat it never gets out of the bilge. You might want to poke around.

I have two Rule pumps with check valves (even though Rule recommends against them because they might become clogged). I find that the check valves not only prevent back flow into the bilge, but also seem to guard against the air lock you mention because they maintain a head in in the line. One of the check valves is a heavy duty bronze model that came with the boat. The other is the Whale model from WM.

One other thought which came to me last weekend when I was heeled far enough over to cause water to come into the cockpit through the cockpit drains is that the drains on my boat are connected to the thruhulls only by that comparatively weak (and now 18 years old) spiral reinforced bilge hose. If that cracked, then water would get into the bilge (possibly leading to sinking if not discovered in time). When I felt around the hose collars, I felt moisture, so they seem to be leaking. Fortunately they are above the waterline most of the time. However, I plan to replace those hoses with something sturdier. From your thruhull photo on the Projects page, I see you have that hose too.

 

[u079721]

Not to change the topic...but I too have worried about those cockpit drain hoses. Not only would a leaking hose let in rainwater, but on my E-38 the outlet is underway when heeled.

I bought some replacement hose a few years back, fully intending to replace those two short sections. But I really can't get to the one on port without major liposuction OR removing the propane locker first. Neither approach appealed to me, so for now I just keep the spare hose on board, thinking I might get to it while at anchor some day if it gets to be a problem.

 

[Geoff Johnson]

I can sympathize, but make sure your Marelon thruhulls are working . . . in case you notice that your boat is sailing a little lower in the water than it used to.

BTW, I did notice rain water in my bilge when I first got the boat. I turned out that things moving around in the lazarette had split one of the hoses.

 

[Loren Beach]

...looks like plastic to me...

Since we are talking above-the-water plastic thruhulls with barbs on the inside, on any given boat they may be Marelon, acetate, nylon, or Lord knows what.


Some of these are a lot more resistant to UV than others are.

Food for thought...


Loren

 

[cruis-n]

Look at the rudder stuffing box/gland

You might want to take a look at the rudder post stuffing box/packing gland. When we get going in a strong breeze, the stern wave comes up to the point where water will slosh out of the rudder post stuffing box/gland if it's not properly adjusted.

In my case, it took me almost 5 years to figure it out.

 

[Martin King]

Plastic hose cuffs on the cockpit drains? Yikes! You want
blue stripe wire reinforced hose that you have to cut with
a hacksaw...you'll sleep better!

By the way, does anyone know of a clean way to do the
holding tank vent? My boat came with a particularly ugly
thru-hull right through the topsides amidships.

Martin

 

[lets_go_sailing]

Check to see that your bilge pump hose has a loop in it that brings it far enough above the waterline when sailing in a stiff breeze and chop. when I replaced my pump and hose I just ran it in the same location thinking that is where it is "supposed" be.
WRONG! after about thirty minutes in 20-25 kts of wind someone asked "is that water supposed to be there". I looked down to see about 8 inches of water, bilge boards, and other misc items all sloshing around in the bottom of the boat. It only took a minute to figure out that it had came in through the bilge pump discharge witch was at that time a foot below water level on port tack.
I re routed the hose to put a large loop, as high as possible and as close to the centerline as possible right before it exits the boat and now I can go back to tracing down other mysterious leaks. Of course this may not be the case with you . but it might be worth a peek. Also you may have some trash in the check valve that could prevent it from closing all the way
Good luck

 

[Loren Beach]

An answer appears...

So the gang goes out tonight to thrash around in 15 to 20 kts again. I wondered if any more water might show itself.
I had checked the rudder shaft and the hose attachment points at the transom, and found no problem.
By golly it must have been all the water sitting in those long hose runs aft, for all three pumps. When we were rail down on each tac k... it caused several quarts to run back into the bilge.

Tomight there was hardly any more water at all.

I guess I worry too much.

In other news we were doing over 7 kt to weather and just under 9 kt with the chute up. All of this in smooth water -- no swells on which to surf...

Great to have summer here, at last!



Loren in Portland, OR

 

[Loren Beach]

Back to the factory system...

Just a wrap-up note that I changed out the Rule centrifigal pump for a new Jabsco pump just before vacation, in July. I also remounted the pump under the front of the aft berth. New bronze pickup in the bilge section right behind the table. New strainer in-line, mounted in the small enclosed area under the bottom of the stove, where the hose passes through on its way aft. New wiring, when I found copper corroding in the original 1988 "boat cable", from the panel to the new pump. Seems to work fine now, with no more worry about back-flooding.

Loren in PDX

 

[stbdtack]

bilge pump.....

A check valve is the best way to keep the water from back flooding if you use centrif pumps. Even if you dont get water from the outside back in, you will always have the water on the uphill side of the hose draining back in when the pump stops running.
Avoid the bronze check valves as they can stick shut with age and corrosion and the pump might not build up enough pressure to force it open. The grey nylon valves Guzzler makes (West Marine) work well. They have a rubber flapper valve and I have used 2 on my Morgan for about 8 years now without any maintenance. Put the check valve right next to the pump preferably in a vertical position with the flow up. The weight of the water will keep the flapper valve closed and not let it dry out when not being used. If you have a problem with airlocks after hard sailing simply drill a tiny hole (1/64" or smaller) in the hose at the outlet of the pump before the checkvalve. Position the hole pointing down as a small stream of water will exit the hole when the pump is running. This will allow any trapped air to escape and prime the impeller. ( the pump moves much more water than will escape the small hole)

 

[Mindscape]

32-3 Lower Bilge

Loren, I don't know how the Olson is constructed but on my 32-3 I have discovered that there is an area lower than the visible bilge where water collects, presumably draining from the visible bilge (possibly up to a gallon). So even if you think the bilge is dry, there is still water to slosh around, although with the deep bilges on my boat it never gets out of the bilge. You might want to poke around.
.

Geoff - have you found a good way to either: prevent water from going into this lower bilge or to pump the water out of this bilge?

 

[Geoff Johnson]

I have not found a way to keep it from going in, but it's easy to pump out with a hand pump through the access hole (for access to the forward keel bolt) in the cabin sole just forward of the mast (hidden by the teak trim in case you haven't found it). I use one of those brass pumps you can get at WM, which allow you to screw a hose on the lower end. At a hardware store I got one of those utility hoses covered by SS wire braid which keeps the hose straight and allows me to lower it striaght down the foot or so to the bottom of that part of the bilge. I then pump the water into a bucket.

 

[Sailsteve]

Water is a funny substance!

Uninvited bilge water! I had the same problem on my E36RH. I'd be motoring for a whole day at hull speed with the back end of the boat sucking down into the water. At the end of the journey I would check the bilge and it would be full of many GALLONS of water. After the initial shock thinking that the boat was sinking I checked the usual suspects ... prop shaft drip? (no problem there); loose through-hull fitting? (nope); someone with a garden hose filling up the boat while I wasn't looking? (no one there but some imaginary friends). So, I determined that the culprit was in fact the Rule bilge pump reverse siphoning water back into the boat because the discharge hole was under the water at top speed (or on starboard tack). To keep this from happening again, I bought a small marelon vented loop fititing and put it in the discharge line a bit higher than maximum water height in any other condiditons short of a knockdown. It seems to have done the trick. Now, if I can only find all of the leaks through deck fitting sources I'll be in great shape.

Other than that I appreciate the good advice about checking those aging hoses all over the back end of the boat. This clearly needs to be done on a 24 year old hull. Big question: Did Ericson employ a group of dwarves to get into that very small below cockpit space to attach those hoses in the first place? I'm 6'5" and have little chance of getting in there to do anything.

Suggestions?

Steve Schwartz
E36RH "Glory Days"

 

[Loren Beach]

Midget boat builders?

AFAIK most all production boats have all their major mechanical and plumbing and wiring done before the deck is put on....
And that's why your water heater will be sooo interesting to replace.


Oddly enough, my Olson appears to have had quite a bit of this stuff done after the hull and deck were attached. I was able to easily remove the old water heater, for instance. It looks like they put the top on, tabbed in the lower-down molded interior sections, and then did the mechanical stuff in stages as the upper interior modules were tabbed in place. Finally, they put in the pre-sewn headliner sections throughout the boat.

Having said that, there are places where they must have had some skinny folks under 5'5" to do some of the installations...


Best,

Loren in PDX

 

[Geoff Johnson]

Au contraire, I remember reading somewhere that everything in an Ericson (at least the Mark III) was taken in through the companionway. With a deck that is fiberglassed the the hull from the inside, you would almost have to do it that way.

 

[Loren Beach]

Assembly notes

Hi Geoff, Your observation seems quite believable. Perhaps major stuff, like the machinery, tanks, and the water heater were placed before the deck was dropped on and glassed/attached. These large item installations could be done right after the TAFG was bonded in place.

FWIW, our deck is different from the Ericsons of the period, being tru-bolted on an inward flange of the top of the hull.
Our boat does not have the TAFG, but does have all the interior modules tabbed completely to the hull and deck. Good for strength, but we miss the extensive teak "furniture" of the regular Ericsons.
"Everything's a compromise," as someone in this group sez...


Best,
Loren in PDX
(ps: it is a pleasure to have such nice group of owners to exchange info with!)

 

[Geoff Johnson]

At the risk of beating a dead or at least moribund horse, from my obervation, everything on my 32-3 except the TFG could be removed through the companionway (like a ship in a bottle). All the tanks are in screw down compartments. Even the bulkheads are bolted to the TFG (although I am not quite sure how they are attached at the top).

 

[Sailsteve]

So, no little men?

I often wondered how all the plumbing and wiring was installed in these boats. I was sure that midgets were involved.

I actually thought that midgets were involved in the ship in a bottle stuff too.

Steve Schwartz
E36RH "Glory Days."

 

[Geoff Johnson]

If the horse wasn't dead before, it sure is now.