Axis Wakeboard Boat Forum

Looks great.

So how do you do this? Did you add extra lines or just add length to the current lines? Do both bags fill/drain at the same time or is it one then the other?

Thanks for the pictures!

I ran an extra long ballast hose from the "front" ballast fill pump that fills the mushroom sack, long enough to reach the new top bow sack (an extra 5' feet or so) The low drain port on the top bow sack drains through a 1" hose (approx 4' long) into the mushroom sack. When I hit "fill" on the front ballast switch, water is pumped into the top of the top bow sack, drains through into the mushroom sack and fills the mushroom, as that sack gets full, the top sack fills. This is how the rear plug n play is set up. So when I hit "drain" on the "front" ballast, water is pumped out of the mushroom sack and gravity drains water out of the top sack into the mushroom sack. I do have to go up there and lift the left side of the U shaped sack to get all the water out, and if I would have gone with a triangle sack I would not have to do this.

When I do not use the top bow sack I hook this long ballast hose back to the mushroom sack, in its original position, and it just has a big loop of extra hose, as seen in the pictures. I can fold up the 750 bow sack and the 4" hose really small and put it in my lockers or under the seats when not in use.

Gotcha, pretty much what I was thinking about by extending the hoses. Great work! One thing I'm confused on...if you have a vent on the lower bag how does it not let all the water out there before filling the upper bag?

I have always been wondering why Axis puts a check valve in the bow fill line? I added a bow bag myself (boat didn't have the plumbing preinstalled) and until now I can't see why I would need one. What I did need was pit a ball valve between the sac drain and the hard tank as the water pressure forced water trough the hard tank drain pump.
Can anybody enlighten me as to why they put in a check valve?

I believe the reason that the top sack is able to fill all the way with the vent on the bottom sack is the height of the vent through port in relation to the height of the water in the top bag. when sitting the vent through hole is higher than the top sack. Where I am running into trouble is when getting up on plane AND when on plane the vent through hole drops below the water level in the top sack, so it begins to drain water out of the vent line, but just a little dribble. My main issue is that the water pressure is forcing water past the drain pump and up and out the drain thru hole. A ball valve like pilot flying mentioned is the fix for that.

Pilotflying. I do not know the reason, but it has something to do with siphoning. Malibu uses anti-siphon loops, that break the vacuum, or one way valves. I do not know for sure if I need it up in the bow but when I added my sacks in the rear, I had to put them in. I would fill up the sacks all the way and when I would turn off the pump, water would drain back out of the top fill line and past the fill pump out the bottom of the boat. This was all while just sitting on my trailer. I believe when you are moving, the moving water across the fill thru hole port on the bottom of the hull will pull water out of your sacks and tank.

That makes sense. I didn't add a second fill pump for the front bag but just put in a Y right after the front anti siphon loop. Probably the factory chose the check valve over an anti siphon loop for the front P&P. Having both seems to be overkill, I don't have any issues with siphon draining.

Here is another picture of the bow bag completely full. I had a hard tome keeping it full on my test run because the pressure of the water of the top bag would push water out the vent and drain lines of the bottom bag, so it was constantly draining when boat was at speed. I added a $5 pac ball valve to the 1" line between the top and bottom bag. Once the bottom bag is full, I then close the valve and top off the top bag. I leave this valve closed until it is time to drain. It worked perfectly, now the bow sack is completely full and they do not drain on their own.

Looks great! I've got some lead I'm going to play around with first in the spring, depending on how I like it I may move forward with this setup and add another bag in the bow. What would you say your full setup weight is? Do you surf or wakeboard with that?

I've found my best surf wave to be with wedge down, all tanks full, 900's full in the rear, front bag full and another bag with ~500lbs full under the observers seat. That way the weight is as far forward as I can get it hidden and also listing slightly to the left as I surf regular. Just curious how much more weight you're running, and if you list it at all?

900 + 1800 + front bag ~400 + addl bag ~500 = 3600 not including wedge/fuel/people/gear.

Im around 4500 lbs and no wedge.

Sumo 900's in rear lockers, 100 lead in each rear locker under the sacks, no more hard tanks = 2100 (guessing that these 900s fill to about 950 in the lockers as they fill to 1000 when completely full)

150 lbs lead behind driver under bench seat all the way back, 250 opposite that under bench seat all the way back = 400

center hard tank full = 500

sumo 950 arrow sack under bow = 700-750?

sumo 750 bow sack on top = 800


I barely surf. Have surfed my boat a hand full of times, but none with my new set up. Old surf set up was no wedge (cuz I do not have one) all hard tanks full, sumo 900 full on surf side, 600 lbs lead in bow. Riding around 10.8 i think. Wave was very rideable and friendly, but nothing to write home about.