Water In Fwd Bilge

[SereneWarrior]

I've got a 1970 MY with the standard bilge/bilge pump setup. My problem is that there is an occasional source of water that collects in the forward bilge. Although it is not a flood, it has sometimes been enough to activate the bilge pump. I fixed one source of water in that bilge last year when I rerouted the A/C evaporator drain pan hose. This water rarely accumulates when the boat is in port, but once in awhile I do get just a little accumulation without getting underway. However, if I run the boat, espcecially if I run it fast (it's all relative...14-15 knots) I will always have an inch or two of water in the forward bilge. I checked last weekend and noticed that at higher speeds the bow wave rises over the discharge for the forward sea chest. Is it possible that I'm getting water backing up into the sea chest and coming in by flowing back through the forward bilge pump discharge hose? I thought the purpose of the sea chest was to prevent just this sort of thing from happening. I've been unable to identify any other sources of water into that bilge. Ideas?

 

[doc g]

The hull to deck joint could be a source ..................................Pat

 

[yachtsmanbill]

I never understood why hatteras ran the hoses direct to the sea chests... Whenever Ive changed hoses Ive always run a long loop to the deck and back down to the discharge. I also had an unused seacock that I needed to rebed this past winter. It was a constant drool. Once apart it was obvious the external mushroom was galvanically wasted and was replaced as well. I now am down to a slite dribble from a dock water connection to the water heater... other than that... LOL ws

 

[rwetherington]

as some of the older Hats put on weight as us older guys do the boat set a little lower in the water as it runs. Try raising the up loop some or put a flapper check valve in the discharge side of your bilge pump. This is quite common in some of the Hats.

 

[REBrueckner]

Roger's post # 4 addresses my own circumstances in a 1972 48 YF. An inline check valve solved my problem.

I also had minor water there from rain water coming in via the windlass opening and from chain water when I anchor frequently...

 

[Pascal]

putting in a check valve in a bilge pump discharge is a disaster waiting to happen. sooner or later, debris will start restricting flow and the day you need the full capacity of your pump, you'll regret it.

it's a bandaid, which belongs on a sea ray. Reason I mention SR is because on some models they use check valves to make up for too small bilges.

if you suspect that water is coming back thru the bilge pump, put a high loop on the line, 18 to 24" above the discharge thru hull in the sea chest.

 

[SereneWarrior]

I had already thought of the check valve solution, but rejected it for precisely the reason Pascal states. I'll buy some hose this weekend and put a high loop in the bilge pump discharge. We'll see if that does it. Thanks to all for your ideas and solutions!

 

[Top Shelf]

I've got a 48 CNV so I'm not sure we have the same set up. But I had an interesting issue with the forward bilge about 3 weeks ago leaving Bimini enroute to Nassau. We were running the boat at ~10 knots ~1200 RPM. Seas were big and out of the SW and we were running north towards North Rock. I noticed the FWD bilge light come on then go out. This happened several times in several minutes. This was quite unusal so I went down to have a look see.

When I opened the hatch I noticed the shower sump was full and the bilge comparment had quite a bit of water in it. I manually tripped both float SW's and the pumps dully came on. Most of the water evacuated. As soon as I let off water came pouring back in via the pump discharge hoses. And Kept coming......

I went into the cockpit and looked forward on the port side. Because of the attitude of the boat and wind driven waves it seemed like there was a standing wave against the bow as we plowed through it. I went up to the bridge put the pump on manual and got the boat on plane. After a couple of minutes I went back to the auto position on the pump. It was fine. When we made North Rock and turned SE we came off plane and pretty much made Nassau at 10 knots with no other issues.

I'm thinking that both pumps kept "recycling" the same water they were trying evacuate or in other words they couldn't overcome the force of the bow wave to push the water out (even though there are scoops on the hull side). Or worse and scarier yet the combination set up a siphon. Pretty wierd and I'm not sure how you'd access the hoses to the inside of the hull. They seem to be as high as they could possibly be without going through the floor and into the stateroom. Thx.