Starting my freshwater flush setup

[Robert Vetrano]

Starting my fwf finally after talking about it for too long. My system is ok for an engine off system and will tap into the OUT port on my seawater pump. Manifold is all Home Depot stuff and will be installed in my transom locker with a quick disconnect for the dockside garden hose. I used 3/4” braided hose from Amazon to run to my engines, and it will reduce down to 5/8” hose and then into the 1/4” NPT fitting on the pump.

The goal is to easily flush when back at the dock and not have to go into the engine room……making it more likely that I’ll flush every single time. More photos to come when finished.

Topic

[Mike Uliasz]

Thanks Rob for the quick reply.

[Rob Schepis]

It’s probably fine as is since it’s only weeping with something like 50-60 psi on it but you do not want to develop an air leak on suction. JB might be overkill but it would certainly do.

[Mike Uliasz]

Been messing with my fresh water flush for the generator and AC. Came up with a mini version for the ARG 750 & 1000 caps with a brass thru bulkhead fitting (3/4 male GHT with GHT brass valves).

Seems to work fine with the rubble seal on the cap other than if thru hole is shut and water pressure on. Then it has a minor leak at the thru cap seal do to the water pressure. With thru hole open it works fine. Guess I can seal and lock the thru cap with JB Weld? J-B Weld WaterWeld Epoxy Putty?

[Mike Uliasz]

Just finished setting up the fresh water flush with the SBM strainer caps, flushing with the seacocks open.

Tapped into the main 1″ PVC water line, replaced the water spigot with 1″ valve to increase the water flow and use 3/4″ garden hose in place of 5/8″ ending up with ~11 gals per minute flow.

50′ – 5/8 hose off water spigot to washing machine connections = 4.4 gals a minute – Bad idea
50′ – 5/8″ hose off water spigot = ~6.3 gals a minute
50′ – 5/8″ hose off 3/4″ MIP to 1″ PVC = ~7.7 gals a minute

25′ – 3/4″ hose off 3/4″ MIP to 1″ PVC = ~11 gals a minute

Nothing fancy, went with the most direct connection to increase flow. I’ll test the salinity in the after coolers once things get back to normal. Have had a massive amount of rain/fresh water from the Tropical Storm and thunder storms this passed week.

[Mike Uliasz]

Going to change up to larger feeds. Ended up with 6.3 gals a minute off the garden hose attached to a spigot and 7.7 gals a minute with the garden hose attached directly to 1″ PVC via 3/4″ fitting. I’ll do the later with a 1″ valve in place of a spigot. Hopefully the increase flow will make a noticeable difference.

[Rob Schepis]

Yes that looks a tad restrictive. Increased length and reduced diameter is the exact recipe for diminished volume/flow…

[Mike Uliasz]

Just set up my fresh water flush with the strainer caps using washing machine braided lines. Don’t think I’m getting enough flow (~4.5 gals a minute) with the reduced diameter from the 6′ washing machine lines. Did the flush with the seacocks open and sampled the water off the bottom of the aftercooler, tasted salty. Need to check the flow with the braided lines off the garden hose, if better go with a garden hose directly to the strainer attached with a female to female connection

Did a little test with salt-a-way:

SB Engine (SMX pump) had bubbles coming out the exhaust in ~ 20 seconds.
Port Engine (Sherwood pump) had bubbles out the exhaust in ~ 30 seconds.

The SB seacock is difficult to get too, with the exhaust setup. Once to close when winterizing and once to open in the spring is enough.

[Robert Vetrano]

I guess I “could” double clamp everything. I didn’t because none of it is below the waterline, and there’s not really any risk of flooding if a hose popped while the boat is unattended. I figured the only weak spot would be a hose bursting while running.

Which begs the questions, how much PSI is a seawater pump putting out? I figured the pumps are more for volume and not pressure? I don’t have a seawater pressure reading on my Vesselview.

[Kevin Lee]

Brad Arrington wrote:

I know a fellow that almost lost his new downeast style boat recently. He had been leaving the AC system on dehumidify while away from the boat. The hoses to the copper AC lines were only single clamped and one came off, flooding the bilge with salt water as the AC pump continued to run. What saved the boat is the water spray tripped a breaker for the AC pump.

Absolutely, Brad. That’s why I double clamp all critical hoses and most other hoses. Here’s a photo of inside Leeway’s A/C hatch.

BTW, I lived on Long Island since birth until moving to FL in 2007. Grew up in Massapequa and spent the twenty-three years before moving in West Babylon. Loved boating there, but don’t miss the short season!

Kevin

[Brad Arrington]

Kevin Lee wrote:

Hi, Robert,

Thanks for the posts. I’ve been following this thread.

You added a run for the A/C. Do you do this each time? Being in FL, I figure you would be running the A/C all the time at the dock, so flushing is of little value. I’m in SWFL, and I set up a manifold system to flush the A/C either with fresh water or, by closing the discharge lines, with recirculating Barnacle Buster. Other than that, I don’t flush the A/C as it’s always running.

I am interested in setting up a flush system for the engines and genset. I would prefer a system like you made so I don’t have to go to the engine room to flush.

Thanks,

Kevin

I know a fellow that almost lost his new downeast style boat recently. He had been leaving the AC system on dehumidify while away from the boat. The hoses to the copper AC lines were only single clamped and one came off, flooding the bilge with salt water as the AC pump continued to run. What saved the boat is the water spray tripped a breaker for the AC pump.

[Brad Arrington]

Robert Vetrano wrote:

Finally got around to finishing my FWF setup and it works great!!! Got the manifold mounted in my transom locker, and put a QD on the hose end so it’s super easy to just throw my hose on there and let ‘er rip. I also have it running to my existing FW setup that was OEM for the air conditioning and the genny.

Just wondering if it would be a good idea to double clamp those hoses?

[Kevin Lee]

Hi, Robert,

Believe me, I know the critters still grow. Just no way to stop it here when the water is 90 degrees or warmer for a good part of the year. I recently heard about the copper pieces. I’m going to pick up a piece of pipe to cut up and place in the basket. Currently, I place bromine tablets in the A/C strainer. I also place a few in the shower pump.

That’s great the manifold saved your weekend. I won’t tell the marina!

Thanks,
Kevin

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Robert Vetrano

[Robert Vetrano]

Hey Kevin,

While the boat does reside behind my house, I do not run the AC when we are not onboard. I have a Home Depot dehumidifier that we pop in the sink and it does great. However, even running the AC fulltime does not prevent growth…..it actually accelerates it as the water flow is now providing fulltime food flowing by for the critters to live on. I put copper pieces from the hardware store in my strainer to combat growth, and they do a great job. Having said that, I do have to backflush one of my AC units semi-frequently as I get muck in the lines that degrade performance. I built another manifold downstream of my seawater pump that facilitates this a bit easier, and I actually plan on tying in my newly routed flush line into this plumbing to make it even easier.

I have used the AC line though to keep the system running on dockwater when we lost our seawater pump on a trip we took (shh….don’t tell the marina,lol)……had we not done that the weekend would have been ruined with no AC!

[Kevin Lee]

Hi, Robert,

Thanks for the posts. I’ve been following this thread.

You added a run for the A/C. Do you do this each time? Being in FL, I figure you would be running the A/C all the time at the dock, so flushing is of little value. I’m in SWFL, and I set up a manifold system to flush the A/C either with fresh water or, by closing the discharge lines, with recirculating Barnacle Buster. Other than that, I don’t flush the A/C as it’s always running.

I am interested in setting up a flush system for the engines and genset. I would prefer a system like you made so I don’t have to go to the engine room to flush.

Thanks,

Kevin

[Robert Vetrano]

Finally got around to finishing my FWF setup and it works great!!! Got the manifold mounted in my transom locker, and put a QD on the hose end so it’s super easy to just throw my hose on there and let ‘er rip. I also have it running to my existing FW setup that was OEM for the air conditioning and the genny.

2 users thanked author for this post.

glenn111, Kevin Lee

[Stephen Oliver]

Good to know..not surprised as long as the smaller diameter only last for a short length.. any longer it will have an impact.. I have just over 10g/min (US gal) from my 3/4 hose at the end… So hopefully it will stay that way. Still undecided as to whether to do engine off or on flushing.. off and teeing into the pump pressure side will give me some grief changing the impeller as I can barely reach it anyway to change it.. it’s about a 2 hour job that requires aftercooler and fuel solenoid removing!

Thanks for doing the test!

Steve

[Robert Vetrano]

Steve……did a 10s test today on both the 3/4” hose, and then 3/4 reducing to 5/8 and then into the 1/4” NPT fitting. The difference, surprisingly was nil. Filled up the bucket almost the same exact amount.

2 users thanked author for this post.

Kevin Lee, Stephen Oliver

[Robert Vetrano]

Steve……I didn’t do that. But, since I was buffing and waxing today, and not finishing my install…..it would certainly be easy enough for me to do as the manifold is still in my garage. It would be an interesting comparison. I’ll do a vid tmrw.

[Stephen Oliver]

Hi Robert

As I’m looking at embarking on this shortly.. have you ddone a flow comparison between the tap and the 1/4 fitting?

If you fill a bucket from the tap and say count to 10 seconds and measure the volume, then do the same via the fitting and see the difference.

I’m thinking of engine off flushing… As I have mufflers but have put drains in them to a sump pump. Mind you with engine off flushing you could flush at any old speed and it wouldn’t matter.. as long as the saltwater is displaced.

Steve

[Robert Vetrano]

Wondering how much water flow actually would be coming out of a 1/4” NPT fitting I decided to test it. I was rather impressed with how much water flow there was!

Here’s the link to YouTube video.

3 users thanked author for this post.

glenn111, Kevin Lee, Tony Athens

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