2000 Carver 406 bilge leak (Diesel engines)

[Summer Place]

Hello,

I have been trying to hunt down a bilge leak for some time and looking for any input.
So far I have:
Ruled out the fresh water system. The pump only turns on when it needs to,
Checked the shaft seal area, everything looks fine.
Found and repaired a leaking rudder shaft seal.
AC water pump flow out for both AC units looks good on through hulls
No leaks at water intakes for engines and generator

Some other notes/observations -
When the boat sits at rest the forward bilge is the low spot and holds the water.
It does not appear that it takes on water after cleaning the bilge and the boat sits at rest.
When I start the motors I can see no leaks in the engine room around the intakes/motors.

It appears the boat takes on water after I take it out for run.
At this point I am thinking a couple of things.
1-water feed to shaft seals - not sure where the connection is that feeds them
2-Condensate drain for AC- not sure where they drain to

Looking for any input/ideas others may have. My bilge used to stay dry!

Thanks

[Viper]

Your AC condensate should be draining into your shower sumps. If they aren't the hoses might be leaking or a sump isn't working and is overflowing.

Have you checked whether the anchor locker drains overboard or into the bilge? If rain is getting in there through the windlass, it's either going overboard or into the bilge.

[g36]

I have a 405. Yes fwd bilge is low at rest. The fwd ac condensate drains to the fwd sump. The salon ac goes directly overboard midship port side fitting near waterline. If you use your galley sink alot you will start having issues with fwd sump pump clogging at this will overflow. I put up with thisand finally got over having to vlean and unclog. For this reason I have rerouted my galley drain to a direct line overboard. You didn't say how much water and does it continue to rise the longer the boat sits? The anchor locker drain is fwd and with the top door closed over the windlass you shodnt have a problem with rain etc. getting in. I've also had times when the aft sump pump for the shower will stop working due to hair around pump. You may also check that for water will find its way fwd over time.. keep us updated

[Summer Place]

Thanks for the feedback, I'll take a look this weekend. Not concerned about the windlasss the door keeps it covered and there is a drain in the compartment. The galley sink also drains directly overboard. Does anyone know where the water pickup is for the shaft seals?
I cant seem to find and I wanted to confirm that connection.
It appears to me that the water is coming into the forward bilge from the backside of the boat and if I clean the bilge it does not pick up water when we are not using it. I'm thinking it's coming in when we are underway or the motors are running? though the outside bilges around the motors are dry.

[Viper]

QR_BBPOST ...Does anyone know where the water pickup is for the shaft seals?...

Usually TEE into the raw water side of exhaust manifolds. Follow the supply hose from the shaft log.

[Delorean6855]

Ugh...I hate water in the bilge. I have a mariner three sixty and I take on water through what appears to be a siphoning effect on one of the bilge pump lines...still don't know which. It only tends to happen in 2-3 foot seas (which is basically everyday off SoCal coast). Calmer waters, no water in the bilge. I have basically resigned myself to expecting to use the shop-vac after every trip outside of the harbor. How are the sea conditions when you go out?

[bud37]

QR_BBPOST Ugh...I hate water in the bilge. I have a mariner three sixty and I take on water through what appears to be a siphoning effect on one of the bilge pump lines...still don't know which. It only tends to happen in 2-3 foot seas (which is basically everyday off SoCal coast). Calmer waters, no water in the bilge. I have basically resigned myself to expecting to use the shop-vac after every trip outside of the harbor. How are the sea conditions when you go out?

A known problem, there were a few older threads about that and a maybe a fix if I remember right. Try a search on here.

I was thinking this could be summerplaces issue as well, worth a look.

[Viper]

Most newer model bilge pumps have check valves in them now to prevent that and back flow of what's left in the line after the pump shuts off. The check valves are mounted in a removable fitting right on the discharge port of the pump. You just have to keep in mind that it's one more thing to look after at winterizing time as there will always be water in the discharge line at the pump that will need to be removed or it'll split the hose in the winter.

[Delorean6855]

QR_BBPOST Most newer model bilge pumps have check valves in them now to prevent that and back flow of what's left in the line after the pump shuts off. The check valves are mounted in a removable fitting right on the discharge port of the pump. You just have to keep in mind that it's one more thing to look after at winterizing time as there will always be water in the discharge line at the pump that will need to be removed or it'll split the hose in the winter.

Ok, I like, I will definitely be replacing all of my bilge pumps. Are there any known issues with the check valve seizing because of salt deposits? How I miss fresh water boating...

[Viper]

I haven't heard any negative industry feedback but we're mostly fresh water up my way.