Ballasts filling when docked

[rwa95]

Hi everyone. I’m new here and have a 2019 R5 Surf. The boat usually sits on the lift when not in use but have it in a slip in town right now so it’s in the water all the time. The last 3 times getting to the boat after it’s been sitting for at least a few hours, the starboard side ballast is full - even though the boat is off and it was empty when docked. It does empty again on starting and using the dash to empty but is concerning.

Any suggestions would be so helpful.

[dsthomas]

That is interesting. I just found out that the ballast pumps have impellers. Cobalt doesn't give any literature on the ballast system except a map showing where the pumps are. I'd definitely call the dealer. Please post when you get it figured out. Others with more knowledge than I may be able to offer a solution. You may try the Malibu forums as well.

[jhnmdahl]

It sounds a little like the ballast pump impeller may be bad or leaking. How accessible is the pump location? Can you see the make/model of the pump? Hard to gauge whether it's a DIY project without knowing more about how the boat's configured.

[Lifelongbtr]

My 2019 would fill and empty randomly when driving and they added hose to create an air gap to prevent it, still happens here and there, but mostly draining from full and not filling now.

[rwa95]

All very helpful. I’m going to call the dealer again and see what they can figure out. It’s going in for some other random service items in early September so will worry about it then, unless I can figure out something in the meantime. Seems like as long as I empty it before getting underway, it stays mostly empty.

Will keep this updated as I figure it out.

[Krob1114]

I would have thought that they would've designed one line to fill and a separate line to empty and put a back flow preventor on each.

[billk2632]

I don't know much about the surf models, but it sounds like it is siphoning water back into the tank, seems there should be either a check valve or siphon break / loop in the line. Same way bilge pumps are done -- without a siphon break, a discharge hose close or below the water line can siphon water back into the boat -- not good! Is there a through hull valve that can be closed?

[dsthomas]

There is a valve to close the tank so nothing can get in, I'd say a good idea to keep that close till you get it figured out.

[rwa95]

Thanks. I did close the valves. Have an appointment at the dealer next Friday to sort it out.