Specific Ballast Q

[Dave K]

Hello everyone,

I am trying to grasp a solution to a potential problem. I'm sure I have read something on it but... I'm using Tsunami pumps

and inbetween the pump and the entry point to fill the bag I was planning to put a PVC one way check value in to prevent water going out through the intake line.

What do I do to prevent water from coming through the thu hull fitting, pump and into the bag automatically by force, once the boat is underway?

Secondly, which thu hull would be better and why??

Thanks for the help

[crescentbar]

Hello everyone,

I am trying to grasp a solution to a potential problem. I'm sure I have read something on it but... I'm using Tsunami pumps

and inbetween the pump and the entry point to fill the bag I was planning to put a PVC one way check value in to prevent water going out through the intake line.

What do I do to prevent water from coming through the thu hull fitting, pump and into the bag automatically by force, once the boat is underway?

Secondly, which thu hull would be better and why??

This first one is what is on my 23LSV with the MLS. I don't know why or if it's better, but it's what I've got. 4 of them. (Or something real similar)

Thanks for the help

[Bill_AirJunky]

I don't even know which thru hull fittings my Vride has. But I imagine the 2nd one is used to help keep out the weeds & grass from being inhaled into it.

[Bobby Light]

The first thru-hull is what our ballast system uses. The other with the sceen is the pickup for the cooling system and actually screws into the bottom of the boat. I'm sure you could use either without a problem. I think the slotted screen look is for keeping leaves and twigs out if cooling system since it' vital to the engine. I'm sure it would cost a little more as well.

Edited February 9, 2008 by 06vlx

[WakeGirl]

Actually, it's a little different. What you've got pictured there has a barbed fitting, but the stock thru hulls have a threaded 3/4" fitting. Ideally, you want threaded because it makes it easier to put a ball valve right at that point. Furthermore, most fittings like you've pictured there that are barbed are not rated for use below the water line. That fitting is much more similar to the type that is used at the exit point for emptying either ballast or bilge water.

To keep water from filling the bag while underway, just put a loop in the line & get the top of the loop as high as possible. That should eliminate the potential problem of auto-filling.

2 problems exist with using the one with the screen. 1) If you put it on so that the screen faces forward, you will always have problems with auto-filling, regardless of whether or not a loop is in the line. 2) If you turn it around with the screen facing rearward, you will have prime problems & I'm speaking from firsthand experience on that one.

EDIT: Here's one through Ski-Dim that sort of illustrates the point:

Link

Edited February 11, 2008 by WakeGirl

[Malibuman]

I used the second one on my ballast project and turned the screen part towards the rear, but newer boats come with the first one. I put a backflow/flapper valve before the bag to prevent emptying. I have shutoffs after entry in case of emergency.

[Dave K]

hey thanks for the help guys

[mcdave]

Do the loop method on the hose as mentioned above. Also, you will need to add a check valve to prevent the bags from siphoning dry while under way.