Wash / Livewell pump - unwanted water flow

[abl1111]

Took my boat out for a spin yesterday - all went great ! Need a prop change and she will be perfect ( from a 24 pitch to a 22 pitch ( Bravo III ). She flies !!! Clocked at 52 mph @ 4800 rpm's

My question: The thru hull pick-up for the livewell/washdown is allowing water to JET through the pump, when the pump is off, and out through a s.s., capped hose fitting. The water is being being shot out the s.s., capped/sealed hose fitting - under enormous pressure. I do have a bronze valve at the intake to open and close the water from getting to the pump ( I like to leave it open all the time )- and I don't want to have to open the engine compartment every time I want to use the washdown...

Any ideas ? My thoughts:

If I leave all as is, I can connect a hose w/ a spray nozzle at the end and hopefully that would prevent the unwanted spray - however the pump itself would still be getting that enormous pressure and blow-by. And there is no guarantee that the hose/nozzle would stop this water pressure.

Or, I can add a gate valve somewhere and that would definitely stop the spray but again, what (-) effect would it have on the pump ?

Thx...

[Capt Chuck]

Alan

I can understand you not wanting to lift your engine cover every time; regardless, the USCG requires a "Seacock Valve" at any thru hull raw water intake. Without one, given the right conditions, you could take on water and sink [img]/images/graemlins/frown.gif[/img]

[Miles Offshore]

Why not install a "spigot" type gate valve from the inside of your inner hull and hard plumb it on the backside to the seacock valve?? This is the way the 78 formula I fish with has his rigged ??

[RS]

I'm not sure I understand your setup right, but I don't think your capped fittings should leak. I'd check the gasket or use teflon tape on threads (if any)

[abl1111]

The set up is plumbed 100% right; valves and all. When the valve is open, which is the way I like to leave it, and I'm under way - the saltwater is being shot into the intake scoop, past the open valve, and through the pump at an enormous rate. There is a cap that 'caps' where a hose would normally be attached to. That cap is not doing anything - the water is blasting by it.

A spigot/gate valve thru the stern wall is the only idea I have thought of to reduce this. But, even though this will prevent water from blasting thru - will this pressurized water do any damage to the pump ( cause it's still getting to that point ) Capice ?

[Trayder]

Your end cap fitting is faulty. Replace it with a SS Spigot like this:



Water flowing through your pump should not do damage.

[Dave Hirshberg]

abl11,
Heres what's wrong. Your hull scoop only has holes or slits on
one end. Thats causing a lot of pressure at high speeds. To relieve this pressure there needs to be a way for some of the water to escape out of the backside of the scoop. You can either elongate the slits in the scoop towards the back or you can drill several 1/4 inch holes in the back cup of the scoop. Don't worry you'll still get pleanty of water and your pump wont cavitate or run dry. These types of scoops are routinely used on generator intakes and other systems that can't take the additional pressure. Personally I'd drill three or four holes in it and see how that works.
Dave.

[abl1111]

Trayder and Dave,

Thx - both good advice !!!

Personally, I cannot believe that the plastic cap does not stop this water flow. At a dead standstill I turned the pump on w/ the cap on and she sprayed everywhere - that cap might be shot - although it does have the rubber washer in it ( it's a brand new Perko )...

If I can pull the boat again - I will either drill holes or grind the slits more aft on the intake scoop ( Dave is this a theory or you know it to help ? )

And, Trayder, I was trying to avoid a valve mounted on the stern of the boat - but if I have to I will. I think the picture you showed is a valve made by White Cap, possibly.

Do you think just attaching a hose w/ a spray nozzle ( closed ) would do the trick too ? I want to try that 1st, rather than install the valve...

Thx guys

[gw204]

Here's my setup:

Clamshell scoop -> bronze seacock -> reinforced hose -> strainer -> reinforced hose -> Shurflo Blaster pump -> garden hose w/ cheap plastic nozzle.

It doesn't leak one bit while running or with the pump turned on and the nozzle closed.

I ran the garden hose directly to the pump as I was in a hurry and didn't have the time to determine where I wanted to mount a spigot.

Fix or replace your cap and you should be OK.

[Trayder]

The spigot I posted is from Gemlux www.gemlux.com

good luck