FW Flushing Options

[Patrick Mangum]

I removed my fuel coolers when I installed SMX pumps.  Looking to start freshwater flushing after each use.  Can I add a bronze T adapter/ball valve in the hose replacing the fuel cooler between the output of the raw water pump and bottom of the aftercooler? From the t-adapter/ball valve I would have water lines going up to quick connects under the port and stbd gunnel for easy access.

I have Southbay strainers (external wedge style).  No internal strainers.  The raw water hoses going from the thru hull to the input of the raw water pump are much harder to reach especially on the port side which is why I’m considering the fuel cooler removal hose location.

Thoughts? 

 

 

Topic

[Dan]

Some thoughts

“Seaboard is working on some new risers/mixers for me now so they will be right”

“I’ve confirmed I have horizontal water lift mufflers so I’ll need to flush with the engine on”

Its unlikely but you may still be able to flush with the engines off if there is enough height over the mufflers and the exhaust outlet is above the waterline. As Seaboard are involved with redesigning your risers/mixers they would know if you have supplied drawings/measurements/pics.

Introducing the fresh water after the pump (engine off) wont flush the pump or the feed hoses,apart from the benefit of flushing for corrosion control supplying fresh water into the intake hose or inboard strainer will control marine growth,in Florida Ive seen partial and complete blockage of the feed hoses from marine growth on multiple boats in a short period of time.

As you don’t have an inboard strainer a bronze tee into the intake hose is an option

Bronze Tee Adapter for Freshwater Flush System

“I’ll use a mini ball valve at the RW pump and run the water line up to the cockpit and have another mini shutoff valve with hose quick connect for easy access up under the gunnel.  If I leave the valve open at the RW pump (on the suction side) and leave the valve in the cockpit under the coaming closed would this work ok?” 

Two valves per engine leaves you susceptible to failure if you leave one open or both closed, and your fresh water flushing would be minimal due to the size of the port on the pump versus the open seacock supplying salt water.There’s many ways to achieve this, but it’s important to keep as simple as you can, messing around with valves and connections topside and below, starting/stopping engines, swapping connections going back and forth would be a recipe for failure in my opinion.

“Seacocks and main raw water pickup hoses are tough to reach in my boat”

The seacocks are a critical safety feature and should be exorcised regularly,the day will come when a hose fails and you cant shut the seacock as it is frozen,closing it when flushing will ensure complete saltwater elimination, kill any marine growth and exercise the seacock.

 

[Gene Fuller]

That 1/4″ fitting sounds pretty small. It would be better to tap into the strainer or the intake line and keep the fittings roughly as large as the hose.

The resulting flow will be a lot fresher than the mixture that would come from feeding through a 1/4″ fitting.

[Patrick Mangum]

I’ve confirmed I have horizontal water lift mufflers so I’ll need to flush with the engine on.

I’m thinking I may introduce the freshwater on the suction side of the raw water pump via the 1/4″ drain fitting (I think it’s 1/4″).  I’ll use a mini ball valve at the RW pump and run the water line up to the cockpit and have another mini shutoff valve with hose quick connect for easy access up under the gunnel.  

What do you guys think?

If I leave the valve open at the RW pump (on the suction side) and leave the valve in the cockpit under the coaming closed would this work ok? 

I’ll leave the seacocks open.  Dock pressure is good.  I realize there are many ways to do this just trying to figure out what will be effective and easy for my setup.  Seacocks and main raw water pickup hoses are tough to reach in my boat.  

 

[Douglas Fairchild]

I replaced the fuel coolers with metal pipes and installed L fittings/Valve and male hose connection.  This allows me to flush my 480CE engines without running engine.   Been using it for two years.  My after coolers have the drains on them for water to drain out.  In the past two years no water has drained out.  I placed a water pressure gauge on top of after cooler where zinc goes in and even with domestic water supply valve at wide open  water pressure read 0.   

[Woo]

It is my video, and 7 years after relaunch, everything is working perfectly and the condition inside the cooling system is superb.

I have attached a picture of the Yamaha waverunner foolproof flushing ports installed in the cockpit – no need to go into a warm engine room, flush engines while we suds the boat.

We can hear the water running down from the mixing elbow, and confirm its flushing through by eyeballing the exhaust outlet.

Also attached is the pic of an aftercooler core sliding out SIX years after last opening it. Works a treat.

2 users thanked author for this post.

Patrick Mangum, Rob Schepis

[Patrick Mangum]

Engine off flushing

Woo,

Seaboard is working on some new risers/mixers for me now so they will be right.  I was hoping to be able to fresh water flush with the engines off and let gravity do its thing.  I only have in-line mufflers.  I need to double check they aren’t in-line lift mufflers but I’m pretty sure they aren’t.  

Woo – is this your video I saw on youtube?  If so, were you happy with the set-up?

[Woo]

What is your exhaust like? <br />If you flushed with engine off, will the water flow freely through the exhaust to the outlet? ie, any water lift mufflers?

[donald roth]

You need to supply the raw water pump with your wash water, so the inlet is typically in the intake line or the strainer lid.

Since you don’t have an inboard strainer, I’d suggest adding a bronze T into the intake line, possibly nearer the seacock, which I’ll assume is in an accessible location.

[Author]

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