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04OUTBACK
04-20-2010, 10:37 AM
So i am going to switch my front sac with one of my back sacks as the back sacs have a fill/drain ports on 1 end and another fitting on top. I plan on running a hose off the top front of the sac to a thru hull fitting. this should allow for venting/burping the sac and also it should flow when the sac is full.

ANy issues with that thought process? as long as the thru hull is above the line of the sac, it should not freely drain, correct?

mmandley
04-20-2010, 12:18 PM
Correct, run the vent off the top of the bag and up near the threw hull and add a Y connector and your golden

sandm
04-20-2010, 12:31 PM
don't forget the check valve to keep the water from rolling back in through the vent as it's draining.

kaneboats
04-20-2010, 01:42 PM
I think I need to do this too. My front bag fills up with air. Can you use the existing thru-hull and a Y connector? If you add a check valve in the vent line, will air push right through it and get out?

sandm
04-20-2010, 01:46 PM
I wouldn't see why not. the water is going to force the air out the first available hole, the venthole. should be a case where once you see water coming out, you're full.

04OUTBACK
04-20-2010, 01:53 PM
my original plan was to add another through hull, but, if I understand correctly,
If I put a check valve on, I can use a Y and use the current drain for front?

Check valve go above or below the y? Above I would assume so it does not flow back down the other side of the Y?

Thanks
Picking up the boat from Winter Jail today hoping to get to work on some of these chores!

kaneboats
04-20-2010, 02:00 PM
I would think it goes below the Y on the vent side. That way, when you pump out, anything that slips down the other side of the Y gets checked. Any air pushed up through the valve that tries to go down the drain side is eventually going to get pushed up by the rising water. This sound right?

mmandley
04-22-2010, 10:34 AM
I got my Vent right before the Threw Hull. This is so no air while trailering the boat fills my bags. Air coming up B side of the Y is not going to down A side very far. It will hit the pump down there and stop. The path of least resistance will still be threw the valve out the threw hull fitting.

kaneboats
04-22-2010, 12:32 PM
Mmm. Good point.

brain_rinse
04-22-2010, 01:16 PM
I have pics of how I installed the wye fitting and check valve for my rear bags in the link in my sig. I did the same thing for the front bags too. So if the bag fills with air while trailering it doesn't matter. As it gets filled with water any air is pushed out the drain thru-hull. And when draining the bags the check valve keeps the water from coming back to the bag thru the vent line.

moombadaze
04-22-2010, 02:00 PM
I think I need to do this too. My front bag fills up with air. Can you use the existing thru-hull and a Y connector? If you add a check valve in the vent line, will air push right through it and get out?


Grab one of the wifes wine bottle corks for the exit thru hull for when your towing, when ya get to the flint pull it out. Simple/cheap

kaneboats
04-22-2010, 02:15 PM
I ought to be able to find one of them around here. :D

cab13367
04-22-2010, 02:42 PM
I got my Vent right before the Threw Hull. This is so no air while trailering the boat fills my bags. Air coming up B side of the Y is not going to down A side very far. It will hit the pump down there and stop. The path of least resistance will still be threw the valve out the threw hull fitting.

Mike,

Did you install a vent line and y it into your evac line, or did u just install a check valve before the thru hull to keep air from filling the bag?

Al

mmandley
04-22-2010, 06:14 PM
Mike,

Did you install a vent line and y it into your evac line, or did u just install a check valve before the thru hull to keep air from filling the bag?

Al

Right now i just have the Vent next to the threw hull and i plan to put the y below that. The Y is for the right leg of my Nose bag. I am planning on putting another threw hull on the starboard side and run the left leg of my nose bag to it.

Most are running 2 threw hulls on the port side but i don't think i need 2 on one side. Course im still planning my nose bag hook ups. As of right now though i have a 1 way check valve on the line right next to the threw hull fitting.

Lots will say and i agree if your vented then you don't need a check valve but none the less i rather spend a couple bucks for a valve and just not have the bags fill will air to begin with.

jasonwm
04-27-2010, 11:43 PM
The reason for the check valve is not to prevent the bag from filling with air, it's to prevent drain water from filling the bag by flowing back into the vent connection. Air will go right past the drain pump, it won't stop air, let alone water.

With a dedicated vent connection on the top of the bag it doesn't matter if air gets in while trailering (which is a big problem with the forward bag).