E34/35 (?) Port/starboard water tanks interconnected wrong?

[sailingdeacon]

Has anyone noticed a water tank problem I have encountered on my 1987 E34? (Could also occur for other similar models.) Water somehow was getting from one tank to the other, but not consistantly. Just when I thought an unused tank should be full, it was not. At other times is was. I think I have found the problem. The overflow hoses from the separate port and starboard tanks are connected to a single overflow spigot at the sink. The connection is low near the bilge. Therefore when the boat heels water goes from one tank to the other. If I am motering the flow never occurs. I am changing the connection to be high up near the spigot. Hopefully this will fix it.

 

[Loren Beach]

Tank vent plumbing...

It sounds like you have indeed found the problem.

In the FWIW dept, our boat was plumbed by the factory with two tanks, each outlet going to a manifold under the galley sink. Nothing spendy, just small plastic ball valves. I can turn "on" either tank or both or neither...

Each tank has a vent from the top on one end (yup, they are Ronco tanks). Each vent line leads to a separate spout over the galley sink and head sink respectively.
Since each tank is close to these respective sinks, it works fine.

Loren
Olson 34 #8

 

[sailingdeacon]

Thanks for the comment. I also have the manifold you described. I have three spigots in the sink (in addition to the standard hot/cold water faucet. One spigot for sea water/ice box drain, one for fresh water foot pump, and the third for the overflow of the two tanks. It could be that a previous owner replumbed all this . Perhaps from the factory, the two tanks each used a single spigot - and the freed up spigot was used for another purpose. On the other hand, the Ericson manual never mentions two different overflow spigots.

 

[Geoff Johnson]

The water tanks on my 32-3 have always been something of a mystery to me; I think you have put you finger on the cause of one of the problems - unexplainable changes in tank levels. Another problem I have is filling my third 20 gal. V-berth tank (a factory option). Water always backs out of the fill hose before the tank is anywhere near full. I know the air release line works, so I am not sure what the problem is. BTW, my overfill lines seem to empty into both the head and the galley sinks.

 

[sailingdeacon]

Thanks Geoff. But what do you mean by the "air release line"? I have a third tank also, but it is not installed. However the hoses are installed. The third tank drain is led to the manifold area, but another hose is not connected at all. I thought there was only one line leading from the bottom of the tank and another from the top (overflow).

 

[Geoff Johnson]

Maybe it's just semantics. Each tank has three hoses attached, one for filling, one for emptying to the manifold under the galley sink, and one for overflow and air release (you couldn't fill or empty it without a line to prevent pressure/vacuum). The air release line from my bow tank connects to the overflow line running from my port tank to the head sink. So there is one hose from the bottom and two to the top. BTW, I noticed my bow tank had black scum inside it so I took it home and installed a 6" Beckson hatch in the top so I could clean it out. I didn't bother with the port and starbord tanks as they look clean.

 

[escapade]

Ah, the things we can learn from others!! I have a 1988 E-34 w/three tanks. Am learning a lot about this beast from others. I wondered about my tanks mysteriously gaining water but wrote it off to forgetfullness!! FWIW my boat is set up the same as yours so I think we can safely assume it's a factory job. Manifold under galley on foot pump does sea water/ice box/ & refrigator. Second foot pump takes water from port side tank. Replaced drain line on reefer & wish the fleas of 1,000 camels on the person that originally installed it. Took my wife & I 2 hours to snake in the new hose. Bud