House water pressure
 

If supplying the sea water pump with house pressure (70lb.) for a fresh water flash blow the seals.

I having the same problem myself
 

If you find out let me know. my raw water pump is leaking and I am trying to find out if I need a pressure regulator and if so what pressure :ernaehrung004:thanks.

Let me know what you find you. I just made similar post.

I am not positive about your individual pump, but normally when you attach pressure to the suction side of a pump, all the pump will do is go into bypass. Should not hurt the pump. You can attach a fire hydrant to a honda 3" pump and open up the hydrant wide open, water will flow through the pump like it is not there, when you crank the pump, the pressure is boosted, and it will take 4 men to hold the hose.

Same thing with a house pressure washer. When you hook up the house hose, water flows through the pump, and out of the wand. When you crank, pressure is boosted.

If you hook up to the boat, water should circulate right out of the place it normally comes out. If water is circulating, you should not have the full 70psi, probably about 30-40psi.
You will only have 70 psi if the flow is not moving, or not circulating.

Hope this helps.

I agree with Mac attack.
Your intake pump should tolerate 70 lbs of pressure. It is helpful not to spike it and don't turn hose to full blast until its running. FYI at 70 mph you have 70 lbs available to the pump.
Jim

excess WP will blow out past the muffs, if that's the flush method.

US1 Fountian
I have a inline unit with a check valve to stop back flow in to the drive.

Exactly