|Pro's and conns using attwood 750 gph pumps for filling ballast system. I was thinking about tapping into the engine scupper intake and using a 750 gph pump to fill and another to empty hoefully through the bilge output. Any thoughts?|
|I use them on my setup 1 to empty (15 minutes) and 1 to fill 20 minutes I elbowed off of the center drain plug |
|Here's the intake I got them from Lowe's 3/4" I believe |
|Here's the Manifold |
|Here's where the first pump comes in to bring water in from the elbow |
|Sorry the above picture is of the drain pump I have one before the bottom valve to fill with|
|Here's the ballast I got them from RV Salvage and Surplus in Elkhart , IN $50 ea. Hold about 300 lbs. each. |
|There is a pump before the manifold to prime that pump you have to move forward.|
|Very cool. |
|Contemplating using 6 attwood pumps(two for each sack) and a scupper intake for keeping them primed. Would I be able to just use one hole below the waterline for filling using three of the pumps or would they starve each other out??|
|There is a manifold system out there designed by the original patent holder for the Launch Pad ballast system. It is designed to accomodate up to 5 centrifugal pumps off a single intake. |
It was featured in a PR piece in Level X magazine recently (I think page 12??!!).
I lent my copy of the mag to a friend and I haven't gotten it back yet. Once I do, I'll post the phone number of the inventor/manufacturer...
|This system is big dollars. The pumps would be fine and actually work awesome with a scoop strainer. It would fill very fast when moving around 20 mph on all pumps, but the one hose with the straightest shot or least resistance will fill the fastest so you have to watch and slow down when they start to get full.|
|Is there a web site for these manifolds?|
|I have searched all over for a good manifold, I finally found a company that makes one, but it is about 100$ and pretty bulky when you put all the solenoid valves on it. I ended up building a PVC manifold for simplicities sake. Somewhere in the old posts, I think it was in the General section, there are links to the site.|
|Here are a few pics of a manifold using the sprinkler valve solenoids. |
|Do you have any backflow problems? |
Any restriction of flow? How long to fill how much?
|I have those same sprinkler valves...a whole lot of restriction going on there, and serious backflow. I just ordered flow-rite valves to replace them. Flow-rite valves have zero restriction, and don't rust either or use electronics to operate.|
|It never occurred to me to use a large gauge PVC manifold off the scupper with Flow-rite stuff after that...DUH!|
|TY - Thanks! Funny side note: The two side solenoids are so close to the middle valve that I had to unscrew the solenoid motor before screwing them on... (a slight oversight in the design phase) |
JM - This is just a "test" manifold I made to see how well the sprinkler valves actually worked, so I do not have any figures on fill times, yet (I should have a something done in the next 1 - 1.5 months). So far I'm very pleased with how well they work. I'm using the 3/4" thread size valves (the valves also come in a 1" thread)
As far as backflow is concerned, I ran a test by running water backwards (from a garden hose) and there was some leakage. Not a whole lot but enough to warrant a 1/2 pound pvc check valve (this will be placed after the pump and before the manifold).