Need Ballast pump and setup recommendations

[Canuckle Head]

I am not 100% positive but Berg's boat is a 2001 Mobius V so I was thinking that it's the same hull size as my 07 OBV. Please correct me if I'm wrong. When I completely fill my 750 it fills the locker completely full from front to back and side to side but there is a bit of space from the top of the bag to the underside of the locker door. So I am not so sure there is much to gain by going to the 1100? I believe the 1100 is the same length as the 750 but is 4" wider and 4" higher.

[Canuckle Head]

http://media.wakemakers.com/tag/jabsco-ballast-pump/

Just to give you a visual of the set up.

This is what I am building except for the y fitting, check valve and thru hull vent. I went with Johnson pumps instead of the Jabsco however.

[Paully]

It is preference.
I run the 1100's. They fill bottom of compartment nicely and shape themselves to area, then all the seams are not at full stretch too. I fill them to ~80-90% and off we go. BIII system is fine and fill/empty times are not bad (10 min each)
Cheapest option for extra discharge is a check valve before pump with a line to the bilge. It is there and works great (good gpm) but you have to get over the fact you are intentionally filling your boat with free water.

Good luck...!

[bergermaister]

Canuckle - Mine is definitely tight front to back, but I've had my 750 in the rear locker and had room to spare top to bottom and side to side. The 1100 I have only gets about 90-95% full I'd guess, but as was already mentioned, conforms to the space. I actually picked up the 1100 on a closeout deal for cheaper than a 750 so I figured what the hell!

I live fairly close to WakeMakers so I can get parts same day which is great. I'm sure I'll be making a few visits there in the coming months. I know it's cheesy, but my temporary solution to unwanted draining through my vent lines was wine corks in the thru hull fittings! I give full credit for that idea from one the guys on here running a MC...

I haven't really experienced any drain back with my "old" Rule fill pump and there are no one way valves or vent backs on it. I'm wondering how much of a problem that will be with the new setup?

With my back compartments so full and tight when the bag(s) are filled I'm sort of wondering if I will have room for vent back loops....

I guess it wouldn't be that big of a deal to hit the fill switch and top off the bags every once in a while but obviously don't want to be thinking about that while we're surfing along.

[Canuckle Head]

Why not put a PVC ball valve between your sac and the vent hole? Once the bag is full you just close the valve and voilà! Just remember to open it before draining. I've also heard of guys routing their vent lines to the opposite side of the hull from the ballast bag as a simple fix.

Dang, I should have gone with the 1100's!

[bergermaister]

That's always an option but part of the goal of this upgrade is to not have to open the engine cover, mess around with valves and pumps, and not forget to take corks out or whatever. I've been doing that all summer and my engine cover is a one piece so it's a pain, especially if doing it with the engine running. Instead I'm looking to flip a couple switches and kick back.

We'd rather be talking smack about the last run, looking at the pics or vid, queue up the next favorite song, digging into the cooler, etc!

Looking at that diagram for the Jabsco setup I hadn't thought about venting off the fill line with the Y splitter, instead of the seperate vent outlet. I could run another through hull fitting up on the side of the boat that would basically be above the bag and cap the existing one going out the back. It basically acts as a gravity fed drain without some sort of intervention.

What about unwanted draining out the drain pumps (seepage?) while the sacs are full and boat is underway - is that ever a problem?

[Canuckle Head]

What about unwanted draining out the drain pumps (seepage?) while the sacs are full and boat is underway - is that ever a problem?

Apparently not with the impellar pumps.

[bergermaister]

Ok, I was thinking with the Tsunamis though. I'm guessing since the one way check valves and vent back loops exist that this could be a problem...

But how big of a problem?

[NCSUmoomba]

I will add a couple of things...

First, I believe that the 2001 Mobius V is a 23 foot boat, isn't it? This would explain the bags fitting better. Also, don't forget that the Tsunami 1200's are that odd 1-1/8" size, and it is almost impossible to find fittings for them. For the 1100# fat sac, theoretical fill time for a T1200 would be 6.6 minutes, with the T800 it would be 9.9 minutes. So if you went with the 800's, you fill time would be about 3.3 minutes longer, but you won't pull your hair out looking for fittings. What we really need is for Attwood to make a T1000 that is a 1" size.

As far as the aerator pumps are concerned, water will seep past the pumps, both in and out in some cases. Especially if the sac is really full, the pressure in it can push the water back out of the sac when you turn off the pump. Some way to stop this is necessary. You can use manual or electric valves, but I think the vented loops are the simplest way, and they operate hands off. However, placement of these loops is important.

I was planning a ballast system for my Outback and was planning on three sacs, with two T800's for each sac with vented loops and either one big thru hull, or one for each pump. I think the parts list for this system added up to over $1200 (without the bags). All of these thru hulls and plumbing and wiring adds up, plus it gets really complicated to install. It is worse in my direct drive because finding room to mount the pumps below the waterline is tough.

I think, if I ever do this, I will go with three of the Johnson pumps. There is less wiring, no vented loops, less thru hulls, and I can mount them anywhere. And since they are 720gph, it will not be noticably slower than the T800's. I am also fairly confident that I will come out a tad bit less expensive in the end.

[Canuckle Head]

Didn't Moomba upgrade the Mobius in 2006 and up until then the hull was/is the same as the OBV?