SkiersChoice Supra / Moomba Gravity Ballast System History

Skiers Choice Supra and Moomba Ballast System

Skier's Choice Ballast System History:

In the early 2000's SkiersChoice offered two automated ballast systems installed at the factory. Dealers were able to order Supra and Moomba boats with the single tank Bertha Ballast System or upgrade to the optional three tank Hippo Ballast System. This was the beginning of wake enhancement and SkiersChoice was at the forefront.

During the 2002 season the Hippo name was dropped when the parts supplier, Hippopotamus Wake Systems, closed their doors. SkiersChoice moved forward with the Bertha name designation. The overall design and components of the system stayed the same.

In 2005 SkiersChoice changed the name to the Gravity ballast system and offered three package options. The Gravity I system consisted of a center ski locker ballast bag only. The Gravity II was a center ski locker ballast bag and an under rear seat bag to optimize the wake behind direct drive boats. The Gravity III system was the ultimate in wake enhancement and included a center ski locker bag and two more rear bags, one in each of the v-drive storage lockers. In 2007 the Moomba Gravity Mobius LS (direct drive) had the option of a Gravity III system that had a split rear tank which allowed for adjustment in weight from port or starboard.

For 2009 the Gravity III ballast system was redesigned to decrease fill and drain times by moving away from the Hippo system. The new ballast system uses a dedicated 1” thru-hull fitting suppling water to three Jabsco Ballast Puppy pumps. The Gravity I system is unchanged and continues to use the Hippo design as per the user manual printed by SkiersChoice.

Ballast Bag Capacities: (Supra and Moomba Custom Fit Ballast Bags) The factory center ski locker sacs in both Supra and Moomba boats are either 400 lbs, or 650 lbs depending on the bow seating configuration. Standard open walk through bow areas have a medium sized ski locker in the middle of the boat. The larger boats have a play pin style bow which has a ton of storage under the giant walk through seat cushion that stretches up under the bow area.

In the beginning the factory rear bags had a capacity of 270 lbs each and were square in shape which took up a lot of space when full. Between 2004 and 2005 the rear ballast bags were increased to 400 lbs and were built longer in length and shorter in height allowing for more rear compartment storage when filled to capacity. This new shape allowed dealers to be competitive with other makes like Malibu that introduced hard tanks under the floor.

The Gravity name has always confused Supra and Moomba owners as to what capacities their bags actually are. The Fly High Gravity Games Rear Sacs (565 lbs.) and Fly High Gravity Games Center Sac (1180 lbs.) were only offered on the Gravity Games Edition boats. To make it even more confusing for consumers many of the SkiersChoice boats say “Official Tow Boat of the Gravity Games” right above the swim platform. The larger bags were made to fit perfectly in the rear lockers and center play pen style bow storage lockers of the Moomba XLV and Supra 24SSV boats. In 2011 when the Supra 242 was introduced we saw a glimpse into the future with one new hard tank located in the bow. We would not see anymore hard tanks until the 2013 Supra SA22 which arrived in late 2012. 2013 is the year when the Moomba LSV, Moomba Mojo, and all Supra models come equipped with 650 lbs ballast bags in the rear lockers from the factory.

2003 – 2008 Gravity III Ballast System Overview: (Supra/Moomba Bag Buster Upgrade Kit 03-08) The Gravity III ballast system is made up of two parts. There is a fill system and a completely separate drain system. These systems are controlled using a 3 way rocker switch located at the helm near the throttle.

The filling system begins with a scooped intake strainer that forces water up into the fill pump whether the boat is sitting still or underway. The thru-hull intake fitting is capped with a manual shut off ball valve that can be closed to prevented water from entering the system in emergency situations. The aerator fill pump (Rule 2000 Pump) is located on top of the ball valve to stay below the water line which helps keep it primed. A short section of hose connects the pump to an in-line water strainer that filters out any debris preventing the solenoid valve from getting forced open. The strainer is connected to a home sprinkler system manifold. Each port off of the manifold had an electronic solenoid sprinkler valve (Orbit Brand).

By selecting fill on any of the ballast switches a relay activates the fill pump and also opens the selected valve allowing water to flow into the bag. The fill system's bottle neck is triggered when multiple bags are filled at one time. The aerator fill pump does not have enough head pressure to force water through the open valves and into each bag efficiency. Each valve is connected to the top port on the ballast bag using a length of 3/4” hose and a Fly High Straight Quick Connect fitting.

On the bottom of each bag is a short section of 3/4” hose which is connected to the inlet on a Rule aerator drain pump. The rear drain pumps are mounted to the lower wall in the motor compartment just far enough away to lose prime leaving standing water in the bags. The center bag drain pump is located close to the port on the bag in the ski locker. The drain system also acts as the overflow since SkiersChoice engineers did not see any reason to add a vent to allow the release of air that would get trapped in the top of the bags. Shop Supra Moomba Gravity III Ballast System Upgrade

2009-2013 Gravity III Ballast System Overview: (Supra/Moomba Bag Buster Upgrade Kit 09-12) The 2009 Gravity ballast system update provided the perfect solution to a problem that had plagued Supra and Moomba owners since the introduction of the Mobius and Launch lines of wakeboard specific boats. The system was a strikingly different design that relied on flexible vane impeller pumps. By implementing this design each self priming Jabsco Ballast Puppy reversible pump is essentially it’s own closed ballast system. No longer did the driver need to be moving in order to prime the fill pump or increase the throttle to lift the bow in order to prime the drain pumps.

Each pump has it's own 1” mushroom style thru-hull fitting in the bottom of the boat with a ball valve right on top for emergencies. If a leak occurs the water source can be shut off. From the intake 1” ballast hose is run to the pump located in the motor compartment. From the other side of the pump 1” hose makes it's way into the rear storage locker and into the bottom of the ballast bag using a Flow-Rite 1” Elbow fitting connected to a Fly High W743 bag fitting. Unlike Supra and Moomba ballast systems of the past the bags are vented. On the top of the bag a Fly High W736 fitting is connected to a Flow-Rite 3/4” Elbow fitting. The smaller 3/4” ballast hose runs up under the wall and is discharged using a 3/4” thru-hull fitting. This allows for both venting of air when filling and overflowing of water when filled to capacity. The system uses Jabsco Artificial Intelligence Timer Modules to control just how long the pumps are run. Since the system both fills and drains out the bottom of the boat, the person at the helm has no idea of when the bags are actually drained. Because SkiersChoice uses ballast bags instead of ballast hard tanks there was no way to monitor the levels of water without an expensive pressure system from CleanMarine. This did in fact become reality when the Supra VISION system was introduced in 2011. The timer modules were ditched for a more integrated system built right into the display that showed a graphical display of time to provide real time ballast bag levels. Around the same time Moomba boats were outfitted with the ability to adjust the timers within the speed control interface. For 2013 every Supra and Moomba boat comes standard with 1" vent lines and newer style 1" thru-hull vent fittings in the hull

2013 Shock and Awe (Supra SA22) For 2013 the new Supra SA 22 foot wake machine comes equipped from the factory with hard ballast with the ability to also piggy back more ballast on top of the factory system. The sub floor “Liquid Lead Ballast” comes in at 900 pounds which is a great base for any rider. The new factory plug and play, “Flex Ballast” system, provides an additional 1,300 pounds. Why stop there when you can add the new Fly High Supra SA Plug & Play Rear Surf Sac for more surf ballast in the rear compartments?

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