Piggyback Kit from Wakemakers will fill but not empty.

[theskunk]

I'm actually about to double up both of my sacks - the first pair has one in the locker, and then I run under the walk-through where some cables run up to another under the rear seat(s) on the port side. The second pairing has one in the ski locker, and then one under the front seats in the nose. I *am* using a pair of the new/upgraded check-valves from wake makers in the rear since the water doesn't really want to pull that well. I'm also having to use a ball-valve once they are full on the starboard side (for when i surf that side) since the 540 I'm using seems to want to continue siphon draining the whole time...

[theskunk]

Here's the upload of my diagram, including plumbing. I run with the factory tanks full on the side that I surf, and the center tank/sack is full for both sides. The front sack is piggy-back off of the center tank, and i simply move it from one side to the other. I've got the sack plumping attachments connected to the front drain area so that i simply roll the sack up and move to the other side (still have to move the anchor, oh well!)

For the back - the 540 in starboard + people seems to be adequate on the corner, and for the port, I'm still trying to get it to clean up a bit. Just found out that a key member of my group really is only able to surf port, so I'm doing my best to figure that part out quickly.

I'm only using one check-valve per side, just to keep the sack from flattening the hard-tank. The center piggy-backs are done with some hose that runs through the center of the sack, loops about 3-4 times, has holes drilled in it, and is tied to the ends via fishing line. Starboard has a ball-valve to prevent siphoning once full and draining. Due to the check-valve, I don't actually have to open the ball-valve to drain, only to fill and to prevent the 540 from filling up with air.

[Evening Shade]

Skunk,
My piggyback kits came with 2 check valves per side. Did you take one out? Where is check valve located in your current set up?

[theskunk]

I took one out and moved it to the other side as I found it not to be necessary for my purposes. See the picture - the check valves are in a pinkish color just above the T so that fresh-vent can get through in the event of a tank collapse. I have the 1PSI check-valves, which allows the sack to suck dry as opposed to only be on gravity assist.

[Evening Shade]

I took one out and moved it to the other side as I found it not to be necessary for my purposes. See the picture - the check valves are in a pinkish color just above the T so that fresh-vent can get through in the event of a tank collapse. I have the 1PSI check-valves, which allows the sack to suck dry as opposed to only be on gravity assist.

Gotcha. It seemed to me that 2 check valves was more than necessary too. My only issue with 2 check valves is that the sac gets so tight with air as it fills that I'm afraid it could burst or press against a sharp edge or point and puncture. Spencer at Wakemakers said that this should improve with time as the check valve on the vent side "breaks in". It should vent air more freely as the sac fills after this initial break in period.

[theskunk]

You have the 'stock' check valves, correct? How are you preventing your sack from accidentally starting a siphon that continues to drain out the side?

[Evening Shade]

I don't know what the 'stock' check valves are. Mine are the ones that came with the kit. They are black, have female threads in both ends and an arrow on them showing the direction of flow and they say 1 psi on them. I haven't noticed any problems with siphoning, but that may be because I don't fill the sacs slam full with water. If I filled them completely full they would be pressing against the rear compartment lid strut bracket which is sharp. I worry that could cause a hole in the sac.

The only issue I have had is how tight the sac gets with air as it fills. It seems like the sac has much more than 1 psi of air pressure that vents poorly. The sac actually gets so tight with air that it seems like it could burst especially if it came in contact with a semi-sharp object. Unfortunately, I haven't had much time to see if the check valves will 'break in' and start venting air at a lower opening pressure

[theskunk]

Okay - if you have the 1psi valves, then that's what's being included in the "new style" kit from them. They aren't cheap, but they work amazingly well.

The "stock" check-valves require no pressure at all to vent, and they are available on the wake makers.com website directly. The ones that you have (and now I have) are not currently listed and you have to call and request them.

I'm sure there will be some form of break in, but I'm truthfully not so sure how much exactly. The venting of the air is a problem, however right now I have a ball-valve at the top of my starboard bag that I simply turn closed once I have everything full, and then leave it until everything is empty, then it's ready to be opened and re-filled again.