Getting ready to start the project and need to get supplies and have a few questions about materials. <BR> <BR>1. Going to use a 1.5" mushroom thru hull on the bottom for fill and drain. Should I get bronze, brass, or stainless? <BR> <BR>2. What kind of tubing should I get to run from the pumps to the bags? <BR> <BR>3. The rear bags I am going to vent into the bilge pump line with check valves, but I will need to drill vent holes for the front bags. What is the smallest diameter thru hull I can get for the front vents? <BR> <BR>4. The main line coming from the inlet will be 1.5", but I am going to T it to the 2 jabsco 18220-8123 pumps with 1" line. Where can I find a T like that or will I need to make one? <BR> <BR>Thats all for now, thanks. <BR>Bill

1. Stainless would be the best of course <BR>2. Flexible PVC is the best or the clear braided hose <BR>3. Use 3/4" vents <BR>4. I made mine and found everything at Lowes <BR>5. <a href="http://www.wakeworld.com/cgi-bin/Discus4/search.cgi" target="_blank">http://www.wakeworld.com/cgi-bin/Discus4/search.cgi</a> (Sorry I had to)

1) Bronze is best for under water, SS for the vents <BR> <BR>2) For hose, you need something very stiff to avoid collapsing shut due to the suction from the pumps. FlexPCV is great, but I've read it's hard to clamp down. The other choice I would rec, is the metal coil reinforced clear PVC hose. For vent hose, you can use a cheaper breaded reinforced hose. <BR> <BR>3) x2 on 3/4". Hose is easy to find in that size and Fly High offers that size sac fittings as well. <BR> <BR>4) <a href="http://www.flexpvc.com" target="_blank">www.flexpvc.com</a> is also a great place to order most all of the plastic fittings you may need for the distribution lines.

"Bronze is best for under water" <BR> Why is that ?

well come to think of it I guess all of my underwater thru-hulls are bronze too

Looking at the flex pvc website. Would the clear braided hose be ok to use? Would it be more flexible than the regular flex pvc or is it the same just clear?

From what I have seen, the clear braided is still able to collapse. Any hose that will not collapse will never be as flexible because it will always hold certain radius, because it will not collapse. <BR> <BR>I just ordered 1" sanitation hose from Boaters World, but after seeing the price difference on the flex pvc site, I am going to send it back and get that.

Check out Shields Multiflex hose: <a href="http://boatfix.com/catalog/607.pdf" target="_blank">http://boatfix.com/catalog/607.pdf</a>

Check out Ebay seller called Powertrack int hose. Cheap and stiff and flexible. Different sizes, this is what I used in my install and am really happy with it.

What about this hose? Think it would be too stiff? Would I need to splice and elbow all the bends? <BR> <BR><a href="http://cgi.ebay.com/PACIFIC-ECHO-710-White-Spa-Flex-Hose-1-PVC-50-Roll_W0QQitemZ300243124022QQcmdZViewItem?_trksid=p 3286.m20.l1116" target="_blank">http://cgi.ebay.com/PACIFIC-ECHO-710-White-Spa-Flex-Hose-1-PVC-50-Roll_W0QQitemZ300243124022QQcmdZViewItem?_trksid=p 3286.m20.l1116</a> <BR> <BR>(Message edited by drknute3 on October 24, 2008)

If you put elbows in your lines it will decrease water flow. The less bends the better.

Gotcha... <BR> <BR>What about good old heater hose for the lines?

Since in my current design I will be filling and draining with reversible pumps, how will I know when the bags are empty? The drain will be in the bottom of the hull.

Figured out the pumps have run dry protection so I will see how that goes. <BR> <BR>So what about heater hose for the fill lines?

My gut feeling is that automotive heater hose will kink at a tight radius and collapse under suction during the drain cycle.

So flex pvc or spa hose seems to be the way I am going to lean. Played around with it a little at Lowe's the other day and seemed very tough to get a barbed fitting in it. Is there a way to loosen up the hose a bit to get the fittings on?

^^^ a heat gun or simple hair dryer will be your best friend. It's actually a good thing that the hose is a tight fit on the barbs, means less clamping force needed to seal.

Thanks for all they help, time to get to work...

One last question... <BR> <BR>I am concerned about running the pumps dry despite the fact they have run dry protection. The 2 rear bags I have decided to vent thru a couple of 3/4" thru hulls above the water line instead of thru the bilge pump hose. Is there a way I can divert the draining water out the vents on the rear bags instead of thru the intake on the bottom? That way I can visualize them being drained. Just curious.

I would think this would work <BR> <BR><img src="http://www.wakeworld.com/MB/Discus/messages/65921/639893.jpg" alt="Upload">

the above design is what i use in my boat, and it works great!

Thanks for the diagram Mike. Think I may need more info though. What I want to do is divert the draining water from the inlet and T it into the vent line from the rear bag. I have 2 bags in the rear and each has its own vent line. I would like to have each pump drain out thru the existing vent line for each rear bag. So the pump for the rear bags drains out one side and the pump for the front bags drains out the other side. Make sense?

Tigemike, <BR> <BR>The shields multiflex hose you referenced at <a href="http://boatfix.com/catalog/607.pdf" target="_blank">http://boatfix.com/catalog/607.pdf</a> <BR>is NOT intended for through hull use. It is the stuff I used for my lines on my ballast system, and I never had a problem with it, and it is tough as nails. Why do they say not to use it on a through hull? Is it not strong enough?

Another description. Each reversible pump has a line that feeds to (or from) the main 1.5" thru hull on the bottom. I would like to divert draining water from these 2 lines and have each one T into the rear bag vent lines so the water exits above the water line (so I can see it) instead of back thru the bottom of the boat where the water comes in. Make sense? <BR> <BR>(Message edited by drknute3 on October 27, 2008)

Bill, <BR> <BR>You can do that, you just add another check valve on the vent line so that water does not go back into the sack and T the drain into it above the check valve. Then the water will flow out through the vent line. .

So the lines coming from the main inlet that feeds each pump would need a check valve so water cant flow back out. Then run a T'ed line starting between the valve and the pump and t into the vent line between the check valve and the thru hull?

Talltigeguy, <BR> <BR>Got me on why it's not recommended for thru-hull use. It is kinda tough to clamp down due to the wire-reinforced coil, this could be why! <BR> <BR>Bill, <BR> <BR>Because you are using 1 pump to fill and drain 2 sacs, you have to "T" off after the pump, in drain mode, so I would just "T" the drain into one of the vents, which ever side is closer. <img src="http://www.wakeworld.com/MB/Discus/messages/65921/639932.jpg" alt="Upload">

How about this diagram?<img src="http://www.wakeworld.com/MB/Discus/messages/65921/639957.jpg" alt="Upload">

When I run the pumps to fill, the pumps are going to suck air through the green lines arent they?

^^^ Yep, but a check valve in each green drain line will fix that. Diag looks good, should work fine.

Thanks. With a check valve in the green line, no air can be pulled back through the line towards the pump. But I dont have to be worried about any water getting pumped into the green line because the pump is after the T? Is that correct? <BR>also, since I am draining out the vent line, should I change the vent from 3/4" to 1" since all the fill/drain lines are 1"? <BR> <BR>(Message edited by drknute3 on October 27, 2008)

In "fill mode" there will be a suction on the green "drain" line, the check valve will create this vacuum. <BR> <BR>I would go go one inch all the way, easier to find 1x1x1 T's over 1x1x3/4. I see no advantage to mixing sizes.

Gotcha thanks for the help. now its time to get to work...

Ok, last question...i swear! <BR> <BR>Since the thru hull on the bottom is only going to be used for filling, would filling on the fly be better with a strainer type inlet instead of a mushroom?

The 1.5" strainer is 4"x 6" and the 1" is much smaller. Would a 1" intake be enough to feed 2 Jabsco's through 1" tubing?

Thoughts?

I would stay with the 1.5 ID thru-hull at least just to be safe. Not sure what the 4x6 measurements are?

Its the overall size of the strainer. Just seemed big to me is all. You think a strainer would be better than a mushroom, or will a mushroom work just fine?

I think either would be fine. I'm running a mushroom because a scoop style strainer will force-feed the aerator pumps with a gate valve to close off after filling. This is not a problem with impeller type pumps.

As long as I will be able to fill on the fly with a mushroom style intake, that would be my preference. Thanks for all your help Mike, I really appreciate it. <BR> <BR>Bill

I'm able to fill fine on the fly without force-fed filling when pumps are off, with the Ballast Puppies, you should not have an issue IMO. <BR> <BR>Take pics and post as you go, it's always great to see other's configurations as every boat is a little different

In response to one of your earlier questions: I did not have a heat gun so I would dip the end of the flex pvc into a pan of boiling hot water for about 30 seconds, then put the barbed fitting into the tubing. <BR> <BR>A hair dryer will not get the tubing soft enough. I wore leather work gloves and was careful to put the pan of water on top of cardboard to protect the carpet. <BR> <BR>The flex pvc is kind of a hassle to work with but is great once its in place. Also a hassle if you have to make a change; you may have to cut it to get a fitting off.

I just did a similar install this spring. I went with the Spa flex hose (like you found on ebay at a great price IMO). I bought a $20 heat gun from Menard's, worth every penny! You just heat the hose up for 30 seconds and you can slip any fitting right in. I found I didn't even need hose clamps b/c as it cools it melts and forms to the ribs on the fitting. I needed to heat it back up just to get it off.

bill, please be sure to take pics and post up progress.