View Full Version : Gravity 4- 07 LSV bow sack install

07-21-2008, 12:23 AM
I've got an 07 LSV and the wake cleans up nicely when you add weight up front in addidtion to the gravity 3 system. I started by adding a 4th sprinkler valve, I used a 1 inch vavle instead of a 3/4 for a little more flow. Then I got 25 ft of reinforced water hose from west marine, I used the same hose Skiers Choice uses because it's proven and a little more resistant to bending. I routed the hose along side the harness and hoses on the fuel tank, the fill hose came out through the harness hole in the drivers footwell and went over the heater to the fill port on the bag. Next I got 2-500 gph aerator pumps from walmart as the empty pumps,One is mounted sideways due to a clearance issue with my sub box, the drivers side empty pump is mounted straight back from the bag right beside the heater. I made the brackets for the pumps out of some galvanized sheetmetal I had laying around the garage I had a spare 2 circuit switch here already so the wiring was super easy, I just took the factory switches out and found which wire turned on the ballast pump when the switch is on. the rest of the wiring was pretty straight forward. I had an extra switch location where a dummy switch(docking light switch-no lights on my boat, but I had the switch anyway) was wired in and it already had a 20 amp breaker, I wired the bilge pumps together and ran a few wires around the boat (this was easy since I put the stereo in I just had to route a cpl of wires along the harness). To plumb the empty hoses I had to cut 1 hole in the boat on the passenger side, and I just used a T to tap into the existing driver side port (I might have to redo this as the center sack and the bow sack dont empty well at the same time). It worked out great, and the fill time is about the same as normal. The spec for the fly high integrated bow sack is 750 lbs, I filled it 98% full, and then the fill port pushes the seat up, that wouldn't have been a problem if they put the fill port on the side instead of the top though. I did have to take out both front cupholders when the bag is full but that appears to be the only drawback.

07-21-2008, 12:42 AM
few more pics of the empty pumps

Parts list

1-1 inch orbit sprinkler valve- home depot
1-1 inch 2 outlet sprinkler valve manifold- home depot
1-fly high integrated bow sack-friends a dealer(if interested he's cheaper than anywhere else online send me a pm)
2-attwood 500 gph aerator pumps- walmart
25 ft- plastic reinforced water hose- west marine- 2nd most expensive part but the home depot hose kinks to easy
2 -3/4 NPT to hose barb adapters-west marine- bilge pumps to empty port hose.
1-2 circuit ballast control switch- Skiers choice
and a few misc odds and ends.

This is a great addition to thes LSV's I wish I would have done it last year, the wake with everything full and 4 ppl is equivalent to 8 ppl and manually adding 2 sack in the front for about 600 extra lbs, and the best part is I can fill and empty from the drivers seat as I'm cruising just like the rest of the system.

07-21-2008, 01:08 PM
Impressive Install!
Thanks for the parts list.

I bet the wake is SWEET with that filled.

07-21-2008, 04:25 PM
that's similar to how I did mine except I drilled a hole in the hull and added another fill pump for it. I don't have to remove my cup holders and it doesn't raise the seat any though. It looks like it fills 100% too. It makes a big difference in these boats. Nice work.

07-21-2008, 07:40 PM
I took the cupholders out to cut the nipple off of the bottom and they didn't stick well again, I'm going to put a brace in between the cupholders to hold the bag further to the front so the cupholders can go back in. Where are your fill and empty ports located, that makes the difference. I used the top port for the fill and the bottom to empty, the bag doesn't hit the seat the fill hose does, and mine does fill all the way with the seat down I just take a little water out to keep the fill port from having alot of pressure on it.

07-21-2008, 10:27 PM
Great post and good work.
Love to see stuff like that!!!

07-21-2008, 11:10 PM
I fill through the top port and empty through the left side bottom. I also ran a vent line to the front center port.

Eric Z
07-22-2008, 10:42 AM
That is some nice work now when are you free to do that to mine.....LOL. I still have sacks in the same spot. It is a pain to drain them. Maybe someday....

07-22-2008, 01:54 PM
Thanks guys, I wanted to add that the complete install cost me less than 350.00 and I have a friend thats a fly-high dealer so if anyone's interested he said he would sell the bow sack for alot cheaper than anywhere else online. just pm me if your interested. He's a fellow moomba owner.

10-01-2008, 02:49 PM
I want to do something similar to this, but want ability to fill only one side at times for surfing... Anyone have any suggestions?
One option would be to have 2 front sacs and put a valve between them to close off one side..

Thoughts, suggestions? I surfed in an XStar recently with the Fly High Pro X Setup (2500lbs on top of factory setup). It was awesome to switch a valve and a switch and quickly have a ballin surf wave..

Thanks for all the leg work and parts list.. this should make the install easy!