Washdown Pickup Placement

[tank1949]

I am installing a gilled bronze water pickup device to the stern of my boat, below water line and just below bottom of boat. Pump is inside and the pickup will be plumed along the outside of the stern and the plumbing will enter boat above the waterline. Should the gill slits face the water pressure side while boat is under way or be in the reverse? I am concerned that when boat is moving at high speeds, the water pressure might enter slits and rupture pump or plumbing, if gill slits face the bow. I don't know if placing slits facing aft would still provide enough water while boat is moving fast.

 

[mike_i]

Mine is installed with the "gills" parallel with the boat. There won't be that much pressure to damage anything. Install a seacock.

 

[tank1949]

Mine is installed with the "gills" parallel with the boat. There won't be that much pressure to damage anything. Install a seacock.

Not real sure what you mean by "parallel." U mean a thru hull pickup? Gills face bow or stern? I have a sea ****.

 

[flashback]

Fwiw I tend to agree with you that for wash down purposes the scoop should face the stern. For engine intake it would be forward..as your hanging it off the stern you probably could easily swap it if needed..

 

[tank1949]

Fwiw I tend to agree with you that for wash down purposes the scoop should face the stern. For engine intake it would be forward..as your hanging it off the stern you probably could easily swap it if needed..

My boat can easily cruse at 30+ and I am afraid that the pressure would blow pump's seals and sink my boat, if gills faced bow.. If my old memory serves me correctly, years ago had a similar installation with gills facing stern and could not use pump while running on plane. I might install an Anti syphon valve in plumbing near pickup, if I decide on gills facing stern.

Thanks to all

 

[dingbat]

Both my raw water and bait well pumps are both on scoop intake facing forward. Pushes water through the pumps at any speed.

Comes in handy on anchor since I don't have to run the bait well pump. Just shut the intake off when not in use.
Has no effect at all on the wash down intake.
Blaster Pro Washdown pump.
Rule Tournament Bait well Pump

 

[tank1949]

Both my raw water and bait well pumps are both on scoop intake facing forward. Pushes water through the pumps at any speed.

Comes in handy on anchor since I don't have to run the bait well pump. Just shut the intake off when not in use.
Has no effect at all on the wash down intake.
Blaster Pro Washdown pump.
Rule Tournament Bait View attachment 378179well Pump

that's exactly what I have, including "Blaster." Thx

 

[Scott Danforth]

most off-shore go-fast fishing boats have a high-speed pickup facing forward, plumbed to a seachest with an overflow line with a check valve to vent excessive pressure

 

[tank1949]

most off-shore go-fast fishing boats have a high-speed pickup facing forward, plumbed to a seachest with an overflow line with a check valve to vent excessive pressure

I was going to install (T in line) a simple lawn sprinkler check valve.

 

[dingbat]

I was going to install (T in line) a simple lawn sprinkler check valve.

All intakes below the water line should have a seacock on the output to the pump.

Unless the lawn sprinkler valve is bronze, and or stainless, your opening yourself up to dissimilar metal corrosion

 

[tank1949]

most off-shore go-fast fishing boats have a high-speed pickup facing forward, plumbed to a seachest with an overflow line with a check valve to vent excessive pressure

I was going to install one of these into plumbing to release too much pressure. It is a simple lawn sprinkler check valve. https://www.lowes.com/pd/AMERICAN-VALVE-PVC-Sch-40-1-2-in-Socket-PVC-In-line-Check-Valve/1000289419

All intakes below the water line should have a seacock on the output to the pump.

Unless the lawn sprinkler valve is bronze, and or stainless, your opening yourself up to dissimilar metal corrosion

Seacock installed. Sprinkler check valve has SS spring. I have used one for over 30 years to hold pressure in my pond source to my sprinkler pump. I will install valve right above gilled pickup. Excessive pressure will force valve open and release pressure that would otherwise go to pump. Yet, pulling from pump will override valve. In theory... I may have to put another check valve inline to maintain washdown pump's prime.