Straightline 4250 GPH Super Max Flow pump for auto ballast system?
 

From what I've found so far this is the fastest pump out there. And I can get a good deal on these, so am thinking of using these for an auto ballast system for my '97 Nautique Super Sport.
Any reason not to? Suggestions?

Wow. That sounds impressive. Better make sure all those hose clamps are extra tight. No way your bilge pump could keep up with that if you sprung a leak while being sidetracked. My biggest concern would be making sure the overflows/vents were sized large enough to handle the overflow.

That pump isn't designed for auto-ballast systems. It's designed to hook into the LINK connection on the top of a Sumo bag.

I used a "Rule 4000" pump for our super sport ballast system. Not 100% familiar with the Straighline, but ours had to be submerged to work ... so we had everything plumbed in to the bags with valves, but the pump still had to get tossed over the side.

We filled ~2300 lbs in like 3-4 mins.

I wonder what pump they are actually using for that Sumo Max pump though? I feel like Straightline didn't design their own pump from scratch? Or maybe they did...

Ronix's 3700GPH pump seems to just be a re-branded Rule 3700GPH pump.

the problem with the high flow rate pumps is that the thru-hull intake would be a bottleneck. Even at 1" or 1-1/4".

so get a 3" thru hull

A 1.25" intake will support one no problem.

Not sure if this is true, but from what I've been told, those extremely high flow pumps will constantly blow fuses on older boats unless you rewire your electrical system. I was told that if you boat is older than a 2013, you will have fuse issues. Again, just what I've been told, haven't personally experienced it.

Age of the boat is not the factor, it is the size/gauge of the wiring going to wherever it is plugged in.

Yeah I'm aware these pumps were not meant for auto-ballast systems, but was wondering if it could be done, and how. Has someone built a system with 'regular' pumps?
It has a 1 3/4" intake port (http://www.slsports.com/accessories-sumo-pumps.html) so it would probably need that size intake.
Wiring might be an issue since it's a '97. Probably not the highest quality wiring, to current standards...

Once of the challenges you have is that the Intake connector is not a permanent threaded connection.

You can probably glue it together with a threaded connection. But it would be a challenge to find something that's going to fit/work.

Then the other challenge is that the LINK adapter on the bag isn't intended to be permanent either. Again, you could glue it in, but that's not ideal. Otherwise you would have to use one of the existing 1" NPT, which would be a bottleneck.

EDIT: Maybe instead of threading the pump directly into the plumbing, you do a 1 3/4" Thru-hull -> 1 3/4" shut-off -> 1 3/4" Hose -> Sump Pump. Similar to how the raw water intakes are done. That way you might have better luck finding suitable intake fittings. I think I even saw 2" thru-hulls on Amazon..

Or you run a piece of tubing from your through hull to the inlet of the pump. Just figure out what size fits over the inlet and double hose clamp it.

Then on the bag side, you can run your hose to multiple inlet/outlet ports so your doubling your through bag area.
If your not to squeamish you can use flow rite's through hull fittings and add 1 1/8" fittings to your bags which flow very well.

You do not have to use their link fittings. They use a hose so, just remove their fitting and put in whatever you need.

yeah the tubing to the inlet was my "second thought" idea... that would definitely work.

good point on splitting it and running to two intakes.

I wonder how this setup would stack up to running dual-tsunami pumps. I know the stated water flow is a lot less, but I wonder with the hose and fitting restrictions if it would end up being similar flow.

Question....Is this pump reversible? If not, how do you plan on emptying the bags? I thought this pump was only designed to flow one direction. Hence throwing it over to fill, then attaching to the bag to empty. I could be wrong though.

He would need different pumps to empty.

Yep. Aerator style pumps are not reversible.

Not a different pump, just a 2nd pump connected directly to the sac outlet.

Yeah it would have 6 pumps, is the idea. Haven't had time to really look into the whole thing yet. Thanks for all the input so far!

With our Rule 4000 setup we had one fill pump ( the rule 4k) then all the empty ports on the bags gravity fed down to where they met at the rear to a Tsunami 1200 that flowed out a single drain I could cap to keep it from trickling out while getting on plane.

Worked pretty well... only needed two pumps

drain time isn't usually the focus, you could drain it all to bilge if you had to.

I've tee'd 2 bags together under bow seats for example and run 1 fill/ 1 drain to both. could do the same in the back depending on you bag layout.

current setup is a fill/drain pump (2 pumps) on each bag. I need to rebuild the stock system in current boat, it doesn't fill fast enough and can't fill underway.

how many bags you putting in?