Piggy back ballast question
 

I have seen post on this in the past I just can't seem to find them now. I added the 750 piggy back system last year to my 2010 nautique 210 and rain fine tell this year. I have crushed my sending unit I guess due to negative pressure. Does anyone have any ideas to help with this. I talked to wake makers and they suggested I could try a t inline before and after the bags and add a check valve on the vent of the bag. The other idea they gave was to just run bags and that might have worked if they mentioned before I bought them so I could have ordered the larger bags. Any help is appreciated.

There are a number of threads on planetnautique with a couple of solutions. The best one is to run a small vent line through the piggyback bag from the hard-tank side to the vent side (of the soft bag). It's a little hard to describe...there are photos on PN.

Basically, your soft bag is sucked dry preventing air from entering the vent side of the hard tank...so vacuum forms which pulls the hard tank in on itself. The sensor is a rigid tube so it gets bent in the process.

What Richard said, here are a couple pics of how mine looks with the tube inside of the tube. One shown tied in and the other still lose.
The quarter inch tube runs from the inlet of the bag through the bag to the outlet or vent line and is tied off at the fittings. This way the bag cannot completely collapse causing vacuum to form in the hard tank.

http://img.tapatalk.com/d/13/05/30/pyva5aru.jpg
http://img.tapatalk.com/d/13/05/30/ehujuqez.jpg