IBS on 2013 LSV

[NateHaskovec]

I like the idea of putting a check valve on the vent so the ballast pump will suck the IBS flat.

My question is, how do you prevent vacuum locking the center tank since it won't collapse (who knows: it might)?

I thought about using a vent on the tank with a float or a vacuum break (check valve backwards) but I wonder if there is another solution I am missing all together.

Anyone have a better way?

[lewisb13]

As per daze, take the line from the hard tank going to a tee. Then on one leg of the tee go to the ibs and from the ibs go to wakemakers check and then thru hull. On the other leg of the tee go to a spring check from lowes and just zip tie it to the line where its connected to the thru hull. Both the ibs and the hard tank will be 99% empty. The reason for two different checks is so that it sucks the ibs dry and then the hard tank has its own check which isnt as strong. Did it on mine and it works great!

[NateHaskovec]

That is what I was talking about when I mentioned a vacuum break. I wouldn't have guessed the spring check would keep from sucking air until the IBS was empty.

You saved me from buying a float vent.

Thanks! And thanks to daze for figuring this out!

[lewisb13]

If you think about it the spring check doesnt even come into play until the bag is empty because the line is wster filled and then the spring check opens and allows the hard tank to vent. You actually have the two check valves checking in different directions.

[NateHaskovec]

If you think about it the spring check doesnt even come into play until the bag is empty because the line is wster filled and then the spring check opens and allows the hard tank to vent. You actually have the two check valves checking in different directions.

Only if you purge the air out of the tube with the "backward" check valve while the tank/IBS are filling. If you don't, the air pocket trapped in there will pull a vacuum when you start pumping.

It sounds like the vacuum isn't strong enough to overcome the pressure from the seating spring on the extra check valve.

[lewisb13]

You start with zero air in the ibs. So as its filling it doesnt need to suck air in