WakeMAKERS Supra/Moomba Gravity III Ballast System Upgrade

Rated 4.5 out of 5
Based on 11 reviews
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WakeMAKERS Supra/Moomba Gravity III Ballast System Upgrade
WakeMAKERS Supra/Moomba Gravity III Ballast System Upgrade
WakeMAKERS Supra/Moomba Gravity III Ballast System Upgrade
Regular price
From $1,199.99

Item: 42103-FH

A complete upgrade for solves all of the issues of the 2002-2008 Moomba and Supra boats equipped with the Gravity III factory ballast system.

Unfortunately, it's well known that the factory Gravity III ballast system installed in 2002-2008 Moomba and Supra boats has numerous flaws in terms of its design and functionality. Going back more than three years ago we pioneered the first Gravity III Ballast System Upgrade, and since then we've helped lots of unhappy owners fix the issues with the factory setup.

The next evolution of that upgrade is this complete package, which includes everything you need, pre-selected and guaranteed to work seamlessly to revamp the factory system that's currently installed in your boat. Our Gravity III Ballast System Upgrade includes everything you need to completely overhaul your factory setup in one convenient package that has been tested through countless installations.

After installation, which we've worked hard to make it as simple as possible, your boat's factory ballast system will essentially be upgraded to the 2009+ factory system which uses a dedicated reversible pump for each bag in the system. That means you can say goodbye to priming issues, slow and inconsistent fill times, and you'll also gain a dedicated vent/overflow connection for each bag. Get more weight in your boat in less time, and with no drama, just an easy to operate system that works like you expect every time.

How It Works

We reuse as much of the factory components as possible to offer value and ease of installation for our customers. Your factory ballast system uses a single common fill pump, which is a huge bottleneck if you are filling all three ballast locations, since the output of that pump is split in thirds.

Our upgrade replaces that single common fill pump with three reversible pumps so that each bag in the system has a dedicated pump for filling and draining. That means you have the full capacity of that pump available to fill each bag, drastically reducing the amount of time required to fill and drain the system.

What's Included

  • 3 WakeMAKERS Premium Reversible Ballast Pumps
  • 20ft. Pump Wiring Harnesses
  • 10ft. Battery Wiring Harnesses
  • Pre-Wired Switch Block Module
  • Battery Terminal Module w/ Fuse Holder
  • 2x 30 Amp Blade Fuses
  • 1" Ballast Hose Black
  • 1" & 1-1/8" Stainless Steel Hose Clamps
  • 3/4" Thread x 1" Hose Barb Fittings
  • Flow-Rite 1" Elbow Quick Release Connectors
  • 3/4" Bronze Ball Valves
  • 3/4" Bronze Mushroom Thru-Hull Intakes
  • Attwood Clear Silicone Marine Adhesive

How It's Installed

Although we've worked as hard as possible to make this upgrade as easy to install as it can possibly be, there are some aspects of the installation that are unavoidable. Let's just get this out of the way right off the bat:

Additional holes will need to be drilled in the boat. There's just no way around it if we're going to fix the problems that are inherent with the factory system.

We've been selling ballast systems for a long time, and our customers are, understandably, always intimidated by this step of the process. We have some great video guides available that demystify this step of the process, so although it's intimidating, if you know how to use a drill, it's not difficult. Of course you can always have your local dealer or marine service shop drill the holes for you if you would prefer (and we're happy to ship your order directly to them for installation).

Outside of the drilling the holes, the rest of the installation is fairly straight forward, and consists of mounting the new pumps, running new hose to feed the system, and wiring the new pumps to your factory switches.

Click here to read our guide on installing Thru-Hull Fittings On Your Boat.

WakeMAKERS Premium Reversible Ballast Pump Wiring Guide
2 Years
Manufacturer Part Number
average rating 4.5 out of 5
Based on 11 reviews
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91% of reviewers would recommend this product to a friend
11 Reviews
Reviewed by Brian R.
Verified Buyer
I recommend this product
Rated 4 out of 5
Review posted

Grav 3 Ballast System Upgrade

Everything was great, service great, installed as it should, only negative was the instructional video and info do not mention at all the front stock ballast bag. Messing with this bag and plumbing a 1" line required taking up the floor, not a huge deal, but also my stock bags have a glued in barb for a 3/4" line, and removing that from the bag can damage the bag requiring replacement. I did find a wakemakers video on removing them after some searching, but was not aware of this issue at time of purchase. Also, the stock bag fill and drain barbs are on the same end of the bag, making using one of them as a vent really not practical, if you swing the bag so the vent is on the high side (towards the bow), then the fill/drain is on the high side as well, and draining the bag is difficult. Leave it on the low (aftward) side of the boat, then the vent doesn't really act as a vent. More discussion on this issue, and perhaps just suggesting a replacement bag size and configuration would be helpful. Great products though, great service, fast delivery.

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Reviewed by J. B.
Verified Reviewer
I recommend this product
Rated 5 out of 5
Review posted

Complete Game Changer for our 2008 Moomba XLV

I bought this boat late summer 2021. I had no idea the stock system was so bad. With the help of an external pump we could have our bags full and ready to go in 30 minutes or so (it was painful). After this upgrade they all fill in about 6 or 7 minutes. They empty just as fast.

I can't say enough good things about the kit. The wiring was as simple as could be. All connections are very secure. All the pumps mounted easily. The 2 thru holes might have been the easiest part of the project. The thru holes are the only time you need a partner.

Just a flat out awesome upgrade. I did upgrade to their bigger Wake Makers bag and we have as good a wave as any of the $100k+ boats out there.

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Reviewed by Rodney W.
Verified Buyer
I recommend this product
Rated 5 out of 5
Review posted

Very satisfied

1st it was a Black Friday deal November 2020 no way to beat that deal Really you’re not going to beat the regular price for all you get. Before doing the install thru hull fittings and ballast pump placement was well thought out (this won’t necessarily be the same for every boat even if they are same model) I didn’t want to place anything where it would create service access issues with other components. The installation was simple (bring your own common sense). This is a very nice upgrade and well worth it worth every penny

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Reviewed by James C.
Verified Buyer
Rated 3 out of 5
Review posted

It looked easy in the Video

I haven't tried the final install yet because 1). not warm enough yet and 2) Still trying to finish the install. I'm almost done. Let me tell you the good parts so far. The electrical wiring and connections require some patience for clean routing but I got it done and the wires were a good length. Drilling holes in the bottom of the boat and installing through holes turned out to be the easiest part of the job.

Not so Good: Anything related to 1" conduit routing and connecting to fittings. Very difficult. A heat gun helps, but sometimes there isn't room to effectively get a heat gun by the hose. Also, I had to pull up the floor panels to rout to the center tank and there is very little room to fit the bigger hose at the turn to the center compartment in a 2008 Moomba. The three ball valves only seemed to screw on to the through hole fittings with a few threads and the handles are long creating interference with other items in the engine area. I bought three new valves a Home depot that worked much better.

Finally, the old ballast has all the fittings cemented in. There is a wakemaker's video on popping out the old fitting after heating with a hair dryer. It worked, but the threads must have been damaged because the new fittings won't secure without feeling stripped. I had to order all new ballast bags that cost almost as much as this pump system. Waiting on the new bags to finish the install.

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Reviewed by Glen M.
Verified Buyer
I recommend this product
Rated 4 out of 5
Review posted

Holy Quick Fill Times!

The kit was great but it took me and my son about 20 hours to install the kit so plan on a full weekend. Also to do it correctly you should pull out the floor which was difficult due to lots of hidden screws. It is screwed in from inside the lockers. Also, in our 23’ XLV we had no hose left over in the end so plan your cuts wisely...start with the longest hoses first. We also decided to run the battery wiring off of the switch so we can shut the system down with the master. Lastly, there is no need to run the wiring around the bow and back to the switch panel. With the floor removed you can run it through the hole in the battery area back to the area in front of the fuel tank then back to the helm area, to the switch panel...there are a few wires from the battery area run this way from the factory. Overall, I’m super happy with the kit and the install and the money I put out for the kit will easily be recovered when I go to sell the boat. The OEM ballast system in this boat takes 25 minutes to fill the 2800lbs ballast and now it takes 7 minutes.

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This product can expose you to chemicals including DINP (Diisononyl phthalate) and DIDP (Diisodecyl phthalate) which are known to the State of California to cause cancer. For more information go to https://www.p65warnings.ca.gov.

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Expert Advice

Our product experts bring over 40+ years of real-world experience and knowledge of the boating industry. They really know the gear, because they spend their free time out on the water with friends and family testing the products out.

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