ballast re....... thru hull ??????

I am redoing my ballast system. I use 4 simer bw85 pumps what size thru hull would you all recommend?

Are you planning to have a single through hull with a tee system set up to feed each pump or are you planning to have a dedicated through hull for each pump. I have (2) 3/4" through hulls dedicated to each of my Jabsco Ballast Puppies. If you only want one through hull then you will want the largest size which I think is a 1 1/4" and then build a PVC Tee system that allows you to give a dedicated intake for each Simer pump. The 1 1/4" intake is expensive and so is the 1 1/4" ball valves and everything else you need to make a viable through hull connection. I chose to do (2) 3/4" intakes because it was more cost effective and actually gave me the capability to intake more water since my total connections is actually 1 1/2" of total intake. Just my 2 cents.

ya, it is set up right now with one thru hull (3/4" strainer)that is plumbed to a manifold that distributes the water to 4 harbor freight marine pumps (crap) but they work. I am changing it for a couple of reasons 1. speed I want to fill and empty quickly each bag. 2. because I don't think the pumps are getting enough water (they kinda gurgle with lots of air). so I am looking to re plumb the intake and I do not want to starve the pumps. 1 1/4" is what the engine has and I was planning on using that size. does anyone think it is to small for 4 pumps (simer bw85).

i dont' the flow rate yada yada on those pumps but they make 1 1/2" THulls

600 gph 10 gpm

bump

for the record it is not 4:00am it is early though.

I have 3 simers running off my fresh water intake on my boat. The hose is only 1" and that also feeds the engine. I haven't had any problems and I have had this setup for 3 years now. I can fill at idle or full speed it doesn't matter and the temp on the boat stays the same and the pumps don't starve as far as I can tell.

Thanks
sbt3- how long does it take to fill?

going with the 1 1/2" scoop strainer

Take me probably 10-15 minutes to fill 3 bags around 650lbs each the fill time is better if I am driving rather than just sitting there. So probably 10 driving and 15 sitting.

I have always used the "mushroom" type thru hull fitting instead of the scoop type fittings. The pumps are self priming, and you don't want water being forced into a scoop style intake if you empty while you are driving.

you'll be happy with the big scoop. or mushroom. the improved flow rate will be nite and day.

Or you could put a fancy drain line on it! lol

My Rival system came with a gigantic 1.5 inch internal diameter through hull. It is a monster. It definitely is overkill when you start to consider the hydrodynamics of things. I think there is something called Bernoulli's principle that I memorized for a test and have since forgotten.