Fresh water flushing Cummins VT555

[Liambennett]

Hi all,
About to start the commissioning of a new Cummins VT555m.
I have two 1000L wing tanks of fresh water.
As the boat may sit for long periods between use I was considering installing a fresh water flush system. Using the tank water as a water source as it will empty the tanks to avoid water sitting in the tanks ( killing 2 birds with one stone )
Was thinking of using a 1 inch hose from each tank plumed into a tee prior to the pump, with ball valves isolating each tank. ( All bronze )
Thoughts ?

 

[Bmarler]

Hi all,
About to start the commissioning of a new Cummins VT555m.
I have two 1000L wing tanks of fresh water.
As the boat may sit for long periods between use I was considering installing a fresh water flush system. Using the tank water as a water source as it will empty the tanks to avoid water sitting in the tanks ( killing 2 birds with one stone )
Was thinking of using a 1 inch hose from each tank plumed into a tee prior to the pump, with ball valves isolating each tank. ( All bronze )
Thoughts ?

Might consider backflow preventers as well.

 

[murofrelwart]

The Groco SSC series is made for this.



https://www.groco.net/products/valves-seacocks/accessories/ssc-series-service-adaptor

 

[DavidM]

There might be an easier way. Look at the attached pic. I drilled and tapped the Perko strainer cap to accept a 1/2" street el. Then I hooked up a ball valve and a hose adapter.

When I want to flush the engine, I hook up a garden hose to the fitting, with the thruhull valve open, I open the water flow, then start the engine. Then close the thruhull and let it flush for 5 minutes or so. Then shut off the water supply and quickly kill the engine. Then open the thruhull.

This will work with the Perko strainer or Groco if it has a bronze top screw on fitting. Don't try it with a plastic fitting.

David

 

[kapnd]

An inline tee at a convenient location between the strainer and pump is a good spot.
1” hose and fittings are probably adequate, but overkill won’t hurt a thing, and may help empty those big tanks quicker.
I have a similar setup, with lots of fresh water to turnover, so I start my freshwater flush about 10 minutes out of the slip, and let it idle for another 10 after tied up.
Putting the valve in an accessible location makes the job a breeze.