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Which way does the sea pump flow ?

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Which way does the sea pump flow ?

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Old 09-16-2002 | 10:26 AM
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Default Which way does the sea pump flow ?

I must have it wrong as it is pressurizeing my water hose and nothing goes though the motor . I was positive it was right . Does the water come out of the top fitting or bottom . One of my pumps is cast in one peice and the other has a 3 peice body that unbolts . Is it possible that if the body was put on backwards it would flow the other way ? I know it shows the flow direction on the pump but I can't see it on the motor .
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Old 09-16-2002 | 10:32 AM
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The oulets on the plastic bodies are labled. You need to look closely at the back of the pump. They are also labled for the reverse rotation motor, so consider your rotation!
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Old 09-16-2002 | 11:30 AM
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I am not sure you can say top or bottom as There is no way to know what way you installed the pump. What generation pump is it? I know that with my Mark 4 stuff I can put the pump in upside down and it will work just fine. Maybe you put the impeller in and when you se the houseing you tuned the impeller wrong. So it you talk off the water pump belt you can just turn the pump in the correct rotation and all the veins will flip. I looked at the spare housing that i have in my boat and there was no real way for me to look at it and explain how it goes. I would just give the engine a quick start and see if the flow is there. If not then swap the hoses and try again. Or get one of those Mechanics Mirrors?

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Old 09-16-2002 | 11:47 AM
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Joe, the outlet is positioned 270 degrees in the direction of rotation AFTER the inlet. You can reverse the direction by changing the inlet and outlet hoses and re-installing the impellor with its veins revesed.
 
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Old 09-16-2002 | 12:32 PM
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Thanks guys . I'm gonna swap the hoses and that should fix it . Just a pane in the ass . I had to take the blower off to even get to the water pump !
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Old 09-16-2002 | 02:17 PM
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Old 09-16-2002 | 02:24 PM
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They flow clockwise in the northern hemisphere and counter-clockwise in the southern hemisphere
The great thing about that is if the boat is upside down it automaticlly starts pumping water out makeing it an Aux bilge pump
 
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Old 09-16-2002 | 03:51 PM
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Is that like digging to China?

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Old 09-16-2002 | 05:00 PM
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Are you guys tellin me the truth ?
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Old 09-16-2002 | 05:34 PM
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Okay, on a vane pump, the inlet and outlet ports will be positioned close to each other inside the pump cavity (as opposed to being on opposite sides of the cavity). They will always be on the side where the impeller gets squished.

If you position the pump so that the shaft is the center of a clock, and the two ports are at 11 oclock and 1 oclock, then the following holds true: Clockwise rotation makes the port at 1 oclock be the INLET and the port at 11 oclock be the OUTLET. Counter Clockwise rotation reverses the ports.

Reason? As the impeller turns, the space between the rubber vanes gets larger as it moves away from the inlet. This causes water to be sucked into the space between the vanes. This water is then carried all the way around the "big side" to the area where the vanes start getting squished again. As they squish, they force water out the outlet. Then the vane crosses the port divider and it starts again. An impeller with 6 vanes is essentially 6 rotating pumps.

Furthermore, the farther apart the ports are from each other the: 1) less volume will be pumped for a given impeller diameter and length. 2) more apt it is to still function acceptably with a missing impeller vane. Like everything else, these designs are a balance of priorities.
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