Plumbed in piggyback sacs

[TxJole]

I've talked myself out of plumbing 2 400lbs sacs in every weekend. Well now my neices boyfriend is getting pretty good at surfing and of course he is goofy when everyone else is regular. I find myself hating more and more swithing sides. Anyreason I should plumb these tanks in ontop of my factory ballast? I'm not going to go any bigger because if i'm not driving I dont trust others with more weight. How long does it take to fill over my tsumnia pump?

[msbowhunter]

Plumb em in and hit the button on the dash. By time you get rope out and board off rack, someone has to take leak, gets a drink and you are ready to surf. When time to drain can do the same, no more plugging in/out and all that. Not to mention can finish draining tank while going down lake or whatever is next.

[Miljack]

If you're going to do it, plumb the 750's in, much better for surfing. You can choose how to much to fill it based on who's driving/surfing the boat!
It's super easy to do on the 210/230's. On my 230 didn't even have to cut the vent hose, just switched it from the tank to the bag.

[TxJole]

Sticking with the 400lbs sacks I have 4 and a few 260lbs, but I did order the kit from wakemakers yesterday.

[krt]

you will like them plumbed in, it's great to hit the switch and fill both the hard tank and bag.

[TxJole]

One question I have is you have to have a vent to drain, while once the sac drains does it not collaspe and close the air flow for draining the hard sac?

[xrichard]

It's so easy to plumb them in and you'll love it so much (just push to fill, push to empty), once you have it done you'll kick yourself for not doing it sooner.

WRT vent, if you let the sac collapse during draining such that no air can get into the hard tank from the vent side, you will collapse the hard tank enough to bend the sending unit. To avoid this, I use the vent at the rear of the fatsac (the one nearest where the water fills the sac) and a stiff rubber bungie cord to hold the vent hose/fitting on the sac up a bit keep it from collapsing flat--that way, air can always pass from the sac's vent to the sac's input (...which is from the vent on the hard tank). I haven't had a problem since I started doing this.

I also tried using both vents on the fat sac and multiple pieces of cross drilled PVC tubes inserted into the sac to keep air flowing...both of these options were ineffective and the fatsac would occasionally get sucked flat.

One other consideration (especially for surfing): If you fill the 400s completely full on top of the hard tanks, they will fill 100% of your available locker space but will also siphon out the vent...so keeping them 100% full is impossible unless: 1. you put in a valve on the vent line and close it once the sac is full in order to prevent siphoning/draining out your vent, or 2. Run the vent hose from the port sac to the starboard side and vice versa.

I did method #1 because my thinking cap malfunctioned. Method 2 looks much better to me and I'll change mine if I ever get around to it.

[TxJole]

I do plan to vent and fill on the same end of the bag simply because I want the beable to roll the sac up to let the carpet under dry up. I have a plumbing supply house, i'm sure I can find a fitting if I have a siphon problem. Truth be told the only reason I order the kit from Wakemakers is to find out the maker of the fitting so I can buy direct. Goal is to make a jumper to connect to factory vent set-up if I want to take the bags out altogether. Thanks for the bungee tip. I will post up a pic of an anti-siphon valve I think I will install if I have a siphon problem.

[Chexi]

If you ever end up selling the 400s for 750s, let me know first. I am looking for a pair of used 400 v-drive sacs.

[shonuff]

Chexi, have you seen this thread in the for sale section?

http://www.planetnautique.com/vb3/sh...-Sacs-for-sale

[HS]

TxJole: On the carpeted tank covers, you'll see they have a 90 up-turn on the aft edge, which I think was designed to prevent items in the locker from falling between the hull and the factory ballst tanks. I cut though the vertical piece with a hole saw to route the existing tank's vent / overflow hose (stub and 90* FH fitting) from the factory tank to the new sac. Otherwise its an "up and over then down" to the fill port on the fat sac. This allowed me to make a clean install and keep the carpet boards in place.

On the new sac vent line, to prevent siphon, I used of the space along the inside wall of the hull above the rub rail (under the gunnel top deck) to create a high spot in the new overflow line.

Now with 750s on each side, wife (who surfs and snowboards right foot forward), has no excuse for sitting out a good surf session . . .and I have less work to do to give her a great surf set up.

[TxJole]

Wakemakers say a piece of 1/2" pvc with holes drilled in it to insure vent flow. I think I will try to get a wiffle ball in my fat sac.

[xrichard]

I did 2x pvc pipes cross drilled in each sac and eventually had problems (once on each side). The pvc pipes help, but you can still collapse the sacks down so air won't flow through...which will then partially collapse your hard tank and bend the sender.

[TxJole]

I not going to do the PVC because I want to roll the bags up. I looked at it more this weekend, think I will drill a hole in the bottom of the carpet board to drain and notch the top of the carpet board to fill and secure the fitting to that to keep the bag from falling flat. Worst case I will add a Watts N36 vacuum relief valve to let it vent, being I have plenty in stock.

[HS]

To avoid this, I use the vent at the rear of the fatsac (the one nearest where the water fills the sac) and a stiff rubber bungie cord to hold the vent hose/fitting on the sac up a bit keep it from collapsing flat--that way, air can always pass from the sac's vent to the sac's input (...which is from the vent on the hard tank). I haven't had a problem since I started doing this.

I like the bungee cord idea.