Aeriator pump system question

I have reversible pumps on my rear sacs, but am thinking of useing aeriator pumps for my sac in the ski locker. will this work?
Im wondering if a ballvalve needs to be installed at the sac to keep it from draining back out thru the bottom of hull.

Looking at your diagram, you are showing a check valve and a ball-valve. The check valve will do what you want when installed as you have it illustrated. The only place I would use a manual ball-valve would be right on the thru-hull, before the pump, as a safety shut off in case of a leak.

Also, if you loop the fill hose higher then the sac, when full, it probably will not drain back and there would be know need to use a check valve. I dont on my rear sacs but due for the front cause the hose runs through the bilge and is lower then the sac.

I would use an impeller pump for fill and aerator for drain.

Aerator issues are: difficult to prime, autofill, autodrain. These things happen on the fill side. Impeller pumps solve all these issues.

Impeller pumps work well but burn up if you allow them to run dry. On the fill side they will never run dry.

I also like the visual feedback of the water shooting out the side of the boat. This arrangement provides that feedback.

TigeMike: I do have a ball valve just past the thru hull where the water comes in.

Honestly, no. Because of where the thru-hull and manifold ended up, I would have to pull the seat box and floor up to get to it..........boat would sink long before

During this off season, I am reconfiguring the intake in order to solve this dilemma. I'm honestly not worried about a leak sinking the boat. With all the fitting below the water line 5200'd and all hoses double clamped, the odds of a failure are slim to none but the piece of mind of having a cut-off is nice.

I have an aerator for my ski locker and it does auto fill because it's so low in the boat. I never worried about it, because it's almost always needed full. Just for the record both setups are great, but aerators are so much better. No prime issues if the intake and manifold is low enough, and the boat motor can be off during filling, silent, fast, and cheap. Can beat that!

Duffy

Same setup I run..
Like TIGEMIKE said just run you fill hoses to the tops of the sacs.

Do the fill hoses have to be at the top of the sac. Mine fill fine from the bottem. I did loop it up higher than the waterline line first though so the sac didn't autofill

^^^ If you fill and drain with a single impeller type reversable, you will use a bottom fitting on the sac/tank.

If you use a separate pump to fill and drain, you will need to full from the top and drain from the bottom.

I use aerator type pumps and it will fill from the bottom.

J,

How does your system drain? Do you have multiple bottom fittings on the sacs?

Yeah each sack of the two rear sack has three fittings. Two on one end and one on the other. The end with two fittings has the factory fly high fittings glued in them. I think you can remove them but I didn't want to mess with it. Anyway that end is towards forward. The bag vents out of the top hole and fills from the bottom one. Drains from the hole on the other end of the bag which is at the bottom.

Gotcha!