water on top of fuel tanks

[bigbill]

1972 58yf i had water on top of my mid and fwd fuel tanks, no water in any of the bilge pump locations... where could this have come from? no smell, i didnt taste it so i dont know if it is salt or fresh, wet vacced about 6 gallons out of the area...we just had a very large rain event 3.5 inches in about 4 hours. i about crapped my pants when i checked the fuel and there was water on top of the tanks, thought she was sinking till i checked the bilges and they only had minimal water in each location...any ideas where to start looking?

[Addie-Kat]

Check your shower sump’s. Not knowing they were not working, had my forward sump overflow for days putting water on top of my tanks. Scared the pants off of me as well.

[meteor64]

On our Yachtfish, any water collecting in that area just stays there, right on top of the fuel tanks. It doesn't drain to the bilge which i find a poor design. We once had water drip from the port engine strainer. Second time this happened, i could not trace the source. Has not happened again for over a year. Fingers crossed! I doubt it would come from the shower sumps as they are way aft under the master bed.

[metama]

Centerline of the Engine room stringers fill that area. I was just chasing a coolant leak that put a few gallons of antifreeze inboard of the stringer.

Also the non-sump "bilges" run back. If you open the hatches in the VIP mid stateroom you can also get access to an area that feeds the top of the tanks. I suspect that if you have a rear drain box issue (Like a cracked shower or aft bilge pump) it could also run into that area.

Has anyone boxed in the tank plates?

The guys where detailing the engines and sprayed a bunch of De-greaser the first time I found this water routing. Bad design.

[Glory]

I would taste the water, I know not everyone wants to do that, salt is likely from the engines.

[Pascal]

Could it be a leak at the connecting hose between the water tank under the midship bunk and the tank under the master floor? Seems like any water on top of the water tank coils migrate forward on top of the fuel tanks especially if the boat is just a little bow heavy. Also that tank in the midship has a vent. If that leaks while filling up the tank you could have water migrating forward. The space on top of the water and fuel tanks communicates, at least on my 53 since that’s how I ran new aft bilge pump wiring a few years back

[bigbill]

dont see any water leaks from the engines,aft shower sump would overflow into the aft bilge, forward sump would overflow into the forward bilge. i will have to check the fresh water tank fill and vent hoses, its not on the fresh water pressure side because the pump is not running thanks for the suggestions....keep um coming

[metama]

Im still voting that it is your sea box in the aft (Same side as the VIP Stateroom) is feeding the water. Any crack in the Aft Sump HOSE, either shower pump hose (Not the shower but the bilge pump hose) or possible the deck scupper drain could get it there. Access should be in the master closet panel.

You know it's not the freshwater tanks if you drain out 1/2 the tank.

[SEVEN]

I found the exit hose from the shower sump pump in the aft stateroom was split in 4 places. Once I replace the hose, I had zero leaks and no more water anywhere in the book. Not sure if that’s your issue but check it out.

[bigbill]

follow up on this problem....after finding the water on the tanks and thinking she was full of water i ran and turned all bilge pumps to the on position, as i checke each engine room then the forward then the aft there was no water in any of them. by the time i made it back to check the aft bilge it must have pumped all of the water out and i ASSUMED it never had any.. fast forward, no water on the tanks but the aft bilge is above the top of the pump. i lifted the auto switch and nothing, put the spare switch in place and still nothing....after some time with the multi meter the line that feeds the auto side of the switch is dead. now my next question, does anybody know the path of this wire? it goes under the master floor and that is as far as i have gotten. before i tear a bunch of stuff up tracing the wire does anybody have the wiring diagram for back in that area? my owners manual does not have that schematic