2 Reversible Pumps vs 1 Reversible???

[goodmatt78]

OK...I have an 05 VLX and I am plumbing in 2 750s in the rear locker.  I was looking at the piggy back, but I don't think it is much more to go reversibles...ie

1) Who has Y'd off 2 reversible pumps from the single drain port under the tranny? (I believe this is 3/4 NPT or 1.05inch OD)

2) Who has Y'd off 2 bags from a single Reversible pump?

Thanks.

 

[smileysteve]

Hi, I have a 2006 Vride, with 2x750lbs in the rear lockers (no stock tanks to piggy back off of). 

I Y'd the two rear bags off of a single Wake Makers reversible pump out of the port engine drain plug 3/4". I mostly followed the logic that you are, if I have a second pump, then i will need to have a bigger or second source of water (and a manifold). The bright side is that they both fill and drain at about the same rate and should be "self leveling", the downside, is the 3/4" and single pump limit my feed filling (I look at 10-15 minutes to fill versus new boats are setup to fill more weight in a 3rd of that time. or less). I also don't have independent control, but have a wake shaper so shouldn't need it.

I feel like adding a second pump is a possibility one winter for the convenience of faster filling ballast, but that will likely also involve an engine compartment relay because the one switch already heats up.

With "just" 750s though, i feel like there are worse scenarios for time to fill; very little of the time will we be surfing with the bags not filled; Though I do alternate slalom sets in or ZUP boarding in; but equipment change takes a few minutes anyway.

Edited April 27, 2020 by smileysteve

[goodmatt78]

Awesome feedback.   Yeah, I wakeboard and that's one reason why I'm not less interested in the piggy back as I like just stock MLS.... Don't need to go killing myself.

Which ballast pump you have?  I was contemplating the larger one at 133 lb/min.

Also, I've never timed my fill time for the mid tank.... So I see no reason to be faster than that.

[smileysteve]

I have the wakemakers premium, looks like the 110lb/min. https://www.wakemakers.com/premium-reversible-ballast-pump.html

My center MLS is definitely faster than my rear, roughly 2x, but it's also vented so requires less timing or watching.

[goodmatt78]

Ok.... This has me back to the 2 pumps off 1 intake.

I know I saw on here sometime had no issues with doing it.  I need to find that thread.

I'm thinking 1 inch hose, 1 inch Y, then 3/4 to each bad.  If I remember correctly from fluid Dynamics, short length restrictions (fittings) have negligible affects on flow.

[MLA]

1) two standard reversible pumps can be run off a single inlet, but IMO, a 3/4" is too small. 3/4 is too small for a single hi-flow.  

2) This will work as long as your goal is to fill and drain them at the same time. A selectable valve  will allow you choose which sac gets filled or drained.  I would not step down to 3/4 hose after the Y, if you go the Y route. Stay with the 1" hose and fittings. 

[wakesonthesnake]

I am sure you are nervous to drill holes in the bottom of your boat but it is not a big deal.  There are good tutorials on Wakemakers site and here.  The little extra cost will be made up for in convenience. I would put two in and leave the drain.  The biggest pain is in the wiring because the reversible pumps draw quite a bit more.  This link is the basic needed stuff although I have always designed my own rather than buying the kits.

 https://www.wakemakers.com/wakemakers-complete-reversible-ballast-system.html

[goodmatt78]

Some of the fittings I need are back ordered.... So I'm going to do the piggy back and then reversibles next winter.  I plan to add 2 1 inch thru hulls up in the mid ship compartment since accessibility is much easier.

[wakesonthesnake]

Mid ship is OK but adds a bit more piping.  You can make it fit by the v-drive with some elbows and good measuring.  Either is a lot better than the drain fitting for two pumps.