Ballast vacuum

I have sacks plumbed on top of all 3 tanks on my 06 Nautique 220. When I drain the ballast, the pumps create a vacuum that pull water through the sacks into the tanks, and then empty out of the tanks. I am having a problem with the sacks completely flattening once they are empty and forming a vacuum which doesnt allow air to pass into the tanks to replace the water when they start to empty. It keeps causing my pumps to flip the breakers.

Has anyone else experienced this type of problem? Any thoughts on a solution? I was thinking of adding a straw of one sort or another in the bag itself to keep it from vacuum locking...

What you need is a vented loop. it will allow air in when needed but will not leak when filling. once I installed them I had no more problems. I have two 3/4 inch one's left over from my install. I ordered the wrong size. I'll sell them for $15 each. paid over $25 each. brand new never used.

A vented loop or just a check valve on a tee set up as a vacuum release is probably the cleanest solution.

When I had an impeller pump system, I had a piece of hose about 2' long with a bunch of cross holes drilled in it that stuck inside each of the sacks. I forget whose idea this was, maybe Ty-one-on? Anyway, it prevented basically the same problem you're having - the outlet getting blocked off by the flattened sack. I wanted them sucked totally flat at the end of the day, and it worked really well.

Check PN for an explanation, but incase anyone else wants it here's a pic of how to get it not to vacum.

Not sure I'd put a ball valve in the overflow line. Too easy to forget you left it closed.

Also, if you fill your bag with PVC, it's no longer as stowable.

I was thinking I could T a fuel overflow/surege valve into each sacks' fill line. when water is flowing in, it should force the valve closed and plug the line up. as soon as the water exits and there is any air in the hose, the valve should remain open creating a vent... the only trick is that the valve has to remain vertical to work...

The valve is not a ball valve. It is a regular vavle. And yes, you need to remeber to open it when emptying.

You only fill enough to cover the width of the bag. You don't need to fill it completely with pvc. Empty it is only 3/4 of an inch taller than a sac without pvc in it. I still have loads of room when they are empty.

Pull the tanks, replace with very large bags.

notidad - I'm guessing the shutoff valve in the overflow line is there because the overflow is at a lower level than you want the sack to fill to? A vented loop can also be used to accomplish the same result, but you won't have to mess with it.

worm - That would work, but plumbing stuff (as opposed to fuel system stuff) would probably be easier to find fittings and such to connect it into the system. You need a swing check valve. 1/2" would be plenty big enough for a vacuum breaker. In the dark grey PVC stuff at Lowe's / HD, they also have these nice tee fittings with big hose barbs on each end, and a small NPT female tap on the side. Been riding much lately? }

"Pull the tanks, replace with very large bags."

yup

scott, flux-

thanks for the wisdom. now i only need to go order the custom sacks to replace the 750 lbers i already have in there. also, i will have to rewire my ballast pumps because they use an in tank sending unit signal as a safety to keep from running the pumps dry. that will also render my ballast gauges completely useless. no big deal to hack it up, it is only a brand new CC 220.

trace-
will check lowes today for what you are talking about...

the 750s are perfect. if the sacks are vented you won't need the guages anyway. just keep the stock tanks and then you can put them back in if you're worred since the boat is new.

they're jabsco pumps right? if so no rewiring would be required. those pumps have a run dry and will not burn up. it's as simple as pulling the tanks and plugging in the bags and maybe adding a foot of new hose to the overflows. unless they're using different pumps. I thought CC also switched over to the jabscos in 06

they are jabscos, but if the ballast gauge reads empty (or no signal at all) from the in tank ballast level pickup, it sends a signal to the pump to not empty (also protecting it from burning up). the only reason i know this is that i have already destroyed one of those ballast pickups because i vacuum locked the tank. i can fill, but to empty, i have do some voodoo rewiring...the in tank pickups are needed to make the pumps run in reverse with the current wiring.

My understanding is that the gauges don't control the shutoff. Dealer told me the pump senses a voltage increase when it gets dry and shuts off. I could be wrong but double check with your dealer. Or maybe Mikeski knows.

when your tanks are completely empty, try running the pumps in the empty direction. my pumps will not turn on at all in the empty direction when the gauges read completely empty.

if the gauges were not part of the circuit, then the pumps would turn on long enough to sense that voltage drop (or rise) then shut off...