Ballast System Planning - '99 SAN

[crobi2]

Hey Chexi! On your manifold system can you fill just one bag without your pump trying to pull air back through the other pumps?

The reason I drilled a 1" for my new through-hull was so I could run 2 impeller pumps off of it one day. Someone - maybe you- calculated that a 1" through-hull was enough for up to 2 pumps.

Anyway, I was wondering if they ever tried to pull air back through other pumps on the manifold if you are running just one pump?

Also, the old factory 3/4" is a scoop type and the 1" that I did is a scoop type. Has anyone had trouble with water pushing past the impeller to fill the bag with the pump off?

The reason I ask is because I still haven't come up with the money for impeller pumps yet, still using aerator style and hand valves alas...

[MI-Nick]

Check out Wake_fun's signature. There is even room for a 1.5" thru-hull, valve, and cross. Some even have 90 degree street elbow in there. Heck, I know a guy who fit that in the motorbox of a 98 Air.

Yes, the drain/fill lines go on the side bottoms of the sacs. Vents off the top.

Be sure you go in reverse with your hole saw while cutting through the gelcoat. Tape the area too with painter's tape first. If you do not do this, you can chip your gelcoat pretty bad. Once you hit glass, you can switch to forward on your drill. You may want to tape the inside too after you drill the pilot hole. I have a friend with a MasterCraft that had the inside top layer of his glass delaminate when drilling a thru-hull. Now that was a MC, so it probably wouldn't happen with a Nautique, but better to be safe than sorry.

I've read wake fun's post and have seen his photos...looks like his intake is near the v-drive though...i'm thinking about going straight up where the current intake is. thanks for the hole saw advice.

[MI-Nick]

When I put in the work to do a ballast install I prefer to do it in a way to get the "optimal" efficiency and performance out of and if your using one thru hull to fill and drain 3 pumps/ sacs you are NOT! I don't understand why people are so afraid of drilling another hole or 2? The new nautiques use 3 seperate thru hulls for a reason, performance and reliability! Do as you wish but I wouldn't even consider tripling up off 1 thru hull but that's just me and the fact in constantly draining port and filling starboard vise versa is a big reason for that sure you can still do that with 1 but I guarantee you will have air locking issues constantly.

optimal efficiency means your system has no more or less than it needs. there is no need to have the capacity to flow 7000GPH if your pumps can only pull 2000GPH...optimum efficiency would mean your intake (and subsequent valves, t's, etc.) flow capacity exactly matches your pumps capacity.
the 1" through hull is rated at 2200GPH (according to wakemakers.com)...3 ballast puppies can pull at most 1920GPH...more like ~1800GPH with ~2' of head...losses from the valve and cross manifold should be < 10%...that means flow capacity ~1980GPH, pump flow rate ~1800GPH...seems pretty well optimized to me.
i'm not afraid of drilling more holes...but, i don't like to get in the habit of doing more than i need...why add more potential points of failure if it's not needed.
if my flow rate/capacity estimates are wrong...of course i'll change...of if anyone has any experience with a single 1" through hull and 3 ballast puppies not working, i'll change.
wake fun reported ~5min fill times with a single 1 1/2" intake...I may go with a single 1 1/4" intake, but even that seems like overkill...

[Chexi]

I never had a problem with air locks on my impeller pumps. If you use aerator pumps, you cannot use a manifold unless you add a bunch of valves into the mix. With impeller pumps, they act as check valves and prevent 99.9% of the water and air from passing, so to the extent it occurrs, it is not a practical problem.

I do agree that having check valves and additional lines so that you can empty out the side where you can see it (instead of back out the intake) is not worth the effort.

Also 1 1/4 is big enough for 3 impeller pumps. 1 inch is just barely big enough. If you want a cushion, go to 1 1/4. Just make sure you have all the fittings and bushing to make the transition. 1 1/2 to 1 is easy. 1 1/4 to 1 is harder to find.

Measure 10 x before you cut and use magnets first to locate your holes.

[crobi2]

Has anyone ever had a scoop type thru-hull force water through an impeller pump to fill the bags when the pump is off?

[Chexi]

I have heard of this happening.

[MI-Nick]

Also 1 1/4 is big enough for 3 impeller pumps. 1 inch is just barely big enough. If you want a cushion, go to 1 1/4. Just make sure you have all the fittings and bushing to make the transition. 1 1/2 to 1 is easy. 1 1/4 to 1 is harder to find.

Measure 10 x before you cut and use magnets first to locate your holes.

this is exactly what i'm thinking about...if I go 1 1/4", i would use a 1 1/4" -> 1" nipple (wakemakers or mcmaster has these) after the valve and into a 1" cross...then 1" 90 hose barbs...my brain tells me 1" will be ok...but i don't know if i want to fly that close to the sun...

[wake_fun]

Post pics when you get going on it

[MI-Nick]

for sure...you'll have to wait till march though...maybe april...although i'm looking out at the lake right now and it's only half frozen...

[vanislwake]

optimal efficiency means your system has no more or less than it needs. there is no need to have the capacity to flow 7000GPH if your pumps can only pull 2000GPH...optimum efficiency would mean your intake (and subsequent valves, t's, etc.) flow capacity exactly matches your pumps capacity.
the 1" through hull is rated at 2200GPH (according to wakemakers.com)...3 ballast puppies can pull at most 1920GPH...more like ~1800GPH with ~2' of head...losses from the valve and cross manifold should be < 10%...that means flow capacity ~1980GPH, pump flow rate ~1800GPH...seems pretty well optimized to me.
i'm not afraid of drilling more holes...but, i don't like to get in the habit of doing more than i need...why add more potential points of failure if it's not needed.
if my flow rate/capacity estimates are wrong...of course i'll change...of if anyone has any experience with a single 1" through hull and 3 ballast puppies not working, i'll change.
wake fun reported ~5min fill times with a single 1 1/2" intake...I may go with a single 1 1/4" intake, but even that seems like overkill...

yes if you think of it that way you are right i used the word efficiency when that wasnt my intended meaning, if you get that? lol Although when i think about it if i'm draining starbpard and filling port at the same time and sharing a common thru hull i'm willing to bet 50-1 odds that seperate thru hulls would be faster!!

If all you ever intend to do is fill then drain all at once i think you are absolutely fine sharing the common thru hull, but i myself always swapping out wait side to side i prefer the method of seperate thru hulls. and to me its less complicated that way too. plus my 02 already has 3 thru hulls from the factory so i dont even need to drill anymore holes in the boat!!

[MI-Nick]

yeah, i'm not worried about the fill and drain at the same time, so i think i'm set on a single through hull. if i already had 3 intakes, i'd use 3 for sure too.

[seth]

Has anyone ever had a scoop type thru-hull force water through an impeller pump to fill the bags when the pump is off?

Yes, this happened to me using the stock intake on my 01 SAN. I used a dremel to cut off the scope portion and the problem was solved. Took 5 minutes.

[Chexi]

I think you have a small error in your plan. You would need a 1 1/4" cross with 3 1" nipples. The cross is the manifold, and you need it to be at the bigger size because it is the last link in the chain before splitting to the 3 pumps. Otherwise, you have done nothing different (flow-wise) from having a 1" thru-hull.

[MI-Nick]

i've been thinking the same thing. mcmaster has 1 1/4" cross and 1 1/4" male -> 1" female reducers...a few more parts, another $10. probably going to start ordering parts this week.

[crobi2]

@ Chexi & Seth - Thanks for the info. I might take a cutoff wheel and try to extend the slots through the solid portion of the scoop and if that doesn't work, just cut off the solid part.

@MI-Nick - If you haven't done it yet I would go with 1 thru-hull per pump if you can. Three discreet little 3/4" thru-hulls with seacoks will take up similar room to the 1 1/4" thru hull with its seacok and 1 1/4" manifold.

If you drill 2 new intakes and use the old one, you probably will have to alter the scoop like we've been talking about. I have also heard of someone who just drilled holes in the solid portion of the scoop to let water go past.

Good luck with your install!