Relocate A/C pump to below the water line

agallant80

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The AC pump and strainer on my boat are both located above the waterline. This is a bit of an issue seeing as the pump is not a self priming and being above the waterline if I forget to close the seacock before pulling the boat on the trailer the pump will lose its prime. I would like to move these things to below the waterline. Does anyone see any issues with having the A/C pump below the waterline?
 

Grub54891

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Re: Relocate A/C pump to below the water line

Nope,see it all the time! Just don't forget to winterize it.
 

smokeonthewater

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Re: Relocate A/C pump to below the water line

Also trace the entire run of the water line from the thru hull to the unit and from the unit to the outlet thru hull.

Make sure there are no low spots that hold water... stead rise from one end to the other and steady drop... that way all water will drain down to the water line) instead of a loop holding water creating an airlock and stopping the pump from priming.

This is more important on boats that are trailered or stored on a boat lift.
 

agallant80

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Re: Relocate A/C pump to below the water line

Going to go down there today to check it out, start moving things. This weekend I had no heat, the pump ran for a bit and got quite hot. Will have to take it apart and see the condition of the impeller.
 

agallant80

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Locate waterline in the engine compartment

Locate waterline in the engine compartment

I am about to move my AC pump below the waterline. What should I use as a reference as to where the waterline is from the inside of the engine compartment? Is there something on the motor that I can look at? Just looking for ideas of how high I can go.
 

smokeonthewater

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Re: Locate waterline in the engine compartment

Re: Locate waterline in the engine compartment

if the boat is in the water connect a hose to the thruhull... hold the other end up and open the valve... lower the hose till you see water... that will be the water level
 

agallant80

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Re: Locate waterline in the engine compartment

Re: Locate waterline in the engine compartment

Its on the trailer.
 

JoLin

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Re: Locate waterline in the engine compartment

Re: Locate waterline in the engine compartment

Its on the trailer.

Measure outside the boat from the gunwale to the waterline, in the same spot (between bow and stern) where the A/C pump will sit. Inside the boat, measure from gunwale to deck, then from deck down into the ER.

Say the outside measurement from gunwale to waterline is 30". Inside the boat, the measurement from gunwale to deck is 24"

You'll want to mount the A/C pump (at least) 6" below deck.

Does that make sense?
 

agallant80

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Re: Relocate A/C pump to below the water line

Does it matter what direction the pump is mounted. Up/down vs flat.
 

smokeonthewater

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Re: Relocate A/C pump to below the water line

I would think that the outlet should be up or at least above the center line to avoid trapped air
if the inlet were at the bottom of the pump it would be more likely to drain and avoid freeze damage if you don't get it attended to before a freeze
 

GA_Boater

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Re: Relocate A/C pump to below the water line

You aren't voiding your warranty, are you? Just curious.
 
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