Inline Inlet between Sea Cock and Strainer

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Tcheairs

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Dec 19, 2023
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32
For winterization purposes with anti freeze in my Crusader (closed cooling system) 350s I'd like to place an inline input for the injection of anti freeze between the sea cock and the (Forespar Marelon) strainers to flush out raw water from the systems for winterization. We frequently have power outages at my marina I've lost Groco strainers and raw water pumps in the past due to freezing.

Does anyone know of such a device (water hose input nozzle) or have fabricated such a device? My raw water intake hoses are quite large and difficult to reach so this will be a difficult installation. Any help or advice would be greatly appreciated.
 
Would something like this Groco device work?


Groco Flush Adapter.jpg
 
Groco makes a Safety Seacock (SSC) with a flushing port, and it can be attacheed either before or after the strainer. Dunno if it might fit your situation. (Peter posted while I was typing.)

TRAC (the Barnacle Buster people) makes a replacement strainer lid for winterizing Groco strainers; don't know if it might fit your situation.

I've read about some folks who've purchased a spare strainer lid for their system, then tapped that and fitted a garden hose input.

-Chris
 
I guess it would. Not exactly clear as to how it connects to the intake shutoff. I'll check with Defender and see how it's done. Thanks for the prompt reply.
 
My strainers are Forespar (marelon material) strainers. Heres a photo. I guess the top of the strainer could be modified to accept a garden hose input. I'm mainly trying to protect my engine raw water pumps, (which I have lost in the past). Seems that the electricity only goes off when the temp drops below 0*...Imagine that!
Forespar Marelon Strainer.jpg
 
The Groco adapter would screw into the Marelon sea strainer, replacing the barbed nipple you currently have connectint the hose between the through-hull valve and the sea strainer. To flush, mix your antifreeze in a 5-gallon bucket and take a short piece of garden hose from the Groco tee to the antifreeze bucket. Close the through-hull and start your engine to pull the antifreeze through your sea strainer and engine. Might want to have a second bucket of antifreeze ready. Also would be wise to have a have a second person to shut-down engine when the bucket is drained. While there would be no issue with not running the antifreeze for a short bit, would be my luck that i'd trip in haste getting out of the engine room.

Good luck -

Peter
 
Just add a tee to the output of the strainer to the raw water pump and add a ball valve. Then you can add a hose connection at the ball valve, or run a hose to a more convenient location and add a hose connection such as this.
 
Great ideas, and this suddenly occurred to me. Place Marelon sanitation Y valve in the system between the raw water seacock and the Marelon strainer. . Connect the water hose connector to the Y valve and this would isolate the raw water intake from the system..I have a closed cooling system and I'm mainly trying to protect my raw water pumps (which I have lost in the past due to electrical outage and no heat to them.
Forespar Marelon Y Valve.jpg
 
I'm mainly trying to protect my engine raw water pumps, (which I have lost in the past). Seems that the electricity only goes off when the temp drops below 0*...Imagine that!

Had you not been winterizing, previously?

-Chris
 
No, I have not been winterizing. Long story short, I had been using temperature controlled 400w heaters in my engine compartment, lost power last year at 0* and it cost me 2 Groco strainers and an engine raw water pump. I can't even get at some of the engine components that require "winterizing" such as the transmission cooler. It's going to be much easier (and more reliable) if I am able to just run antifreeze through the whole raw water system.
 
When we were winterizing I used a Sea Flush adapter that you insert into the strainer. Then fill a 5 gallon bucket with antifreeze and the engine will suck the antifreeze in. Takes about 5 minutes per engine to winterize it.
 
My boat is a 51' Bluewater Coastal. The starboard engine is located under the kitchen counter with less than a foot of crawl space and the strainer is located on the outboard side of the motor. And my strainers are Forespar Marelons (pictured above) likely will not accept the Sea Flush you stick down in your Groco.
 
My boat is a 51' Bluewater Coastal. The starboard engine is located under the kitchen counter with less than a foot of crawl space and the strainer is located on the outboard side of the motor. And my strainers are Forespar Marelons (pictured above) likely will not accept the Sea Flush you stick down in your Groco.
That is too bad because the Sea Flush is a great way to winterize or flush the engine. I have used it to introduce Barnacle Buster into the engines.
 
I did a training lesson on a blue water many years ago. I've seen generator sound enclosures that were bigger than the engine space. Slight exaggeration, but I don't think a ream of paper would fit between the engines.

Sure is a liveable layout. Still conjures up doing a cannonball dive off the top deck.

Peter
 
In March of 2015, I purchased 3 quick flush kits from Marine Technologies Group, 1 each for my Diesel Engine, Diesel Generator, and Cruisair DX systems. The kits facilitate engine flushing and winterizing tasks without having to disconnect inlet hoses. In all cases, I installed the flush kit after the strainer.
Their website is as follows:
 
Can your seacocks be drained when closed, i.e., do they have drain plugs? If not, this will be a challenge because if you close them and don't drain the water trapped within, and it freezes, the valve body will likely crack. Not all seacocks have drain plugs, Groco BV series valves and some others do. See page 84 of this article. https://stevedmarineconsulting.com/wp-content/uploads/2014/03/Seacocks114_cropped.pdf

If you can drain the valves, you can winterize the strainer and engine by first flushing with fresh water, you can do this by closing the seacock, and while the engine is running letting a garden hose flow into the top of the open strainer, let it overflow so you are sure you are providing enough water. Stop the engine, turn off the water. Then fill the strainer with non tox anti-freeze, and restart the engine and keep pouring non-tox in until a good solid stream of it comes out the exhaust. Drain the seacock and the raw water system is winterized. If your muffler can be drained (this is a requirement for ABYC compliance) then drain that after your fresh water flush and before running on non-tox, as there will be less dilution.

More on winterization technique here https://stevedmarineconsulting.com/wp-content/uploads/2020/07/Winterizing-your-Vessel.pdf
 
For winterization purposes with anti freeze in my Crusader (closed cooling system) 350s I'd like to place an inline input for the injection of anti freeze between the sea cock and the (Forespar Marelon) strainers to flush out raw water from the systems for winterization. We frequently have power outages at my marina I've lost Groco strainers and raw water pumps in the past due to freezing.

Does anyone know of such a device (water hose input nozzle) or have fabricated such a device? My raw water intake hoses are quite large and difficult to reach so this will be a difficult installation. Any help or advice would be greatly appreciated.
Just as important to me after cruising the Erie, Rideau and Chambly canals this summer is a way to backwash the strainer seacock. Twice during the summer, my intake got clogged with grass and weeds. The strainer was clean, but the intake on the hull was clogged. Diving worked once to pull grass out of the intake, but I had to backwash the second time with a dock hose. As I didn't have a fitting like this, I took a bath shoving a hose into the seacock opening. It worked, but was a messy job.
 
We have a setup that works really well for both descaling and backflushing. Between the A/C seacock and strainer we have a "T" with a riser, ball valve, and threaded cap (all bronze). Between the "T" and the strainer is another ball valve. While I use it for descaling, I don't see why it wouldn't work for antifreeze.

For descaling, I remove the cap and connect a hose which leads to my Barnacle Buster bucket and pump. Opening the ball valve on the riser allows me to pump through the system (the overboard thruhull lines are also routed to this bucket for running the descaler).

In the event I need to back flush the seacock I close the valve between the "T" and the strainer and flush to the seacock. Rather than use a garden hose,I made a clamp-on adapter and use our bellows dinghy pump to blow the seacock clear. Works great for grass clumps and jellyfish... In theory, by closing one valve and opening the other, I should also be able to pump air through the other way and clear the whole system, but I haven't seen a need for that.
 
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We have a setup that works really well for both descaling and backflushing. Between the A/C seacock and strainer we have a "T" with a riser, ball valve, and threaded cap (all bronze). Between the "T" and the strainer is another ball valve. While I use it for descaling, I don't see why it wouldn't work for antifreeze.

For descaling, I remove the cap and connect a hose which leads to my Barnacle Buster bucket and pump. Opening the ball valve on the riser allows me to pump through the system (the overboard thruhull lines are also routed to this bucket for running the descaler).

In the event I need to back flush the seacock I close the valve between the "T" and the strainer and flush to the seacock. Rather than use a garden hose,I made a clamp-on adapter and use our bellows dinghy pump to blow the seacock clear. Works great for grass clumps and jellyfish... In theory, by closing one valve and opening the other, I should also be able to pump air through the other way and clear the whole system, but I haven't seen a need for that.
I would like to have a similar tee in the line for my engines. My problem is that I cannot find fittings in bronze. Specifically, I need a tee with 1-1/4 hose barbs and a pipe-threaded branch connection. I have looked everywhere.
 
I drilled and tapped three strainer lids, engine, generator and ac. Then ran hoses to garden manifold with valves. Now when I fresh water flush I run a hose to the manifold and pick the one I want to flush. I close the sea cock while flushing. Can also use a short hose from a jug of antifreeze to the manifold for winterizing.
 
I would like to have a similar tee in the line for my engines. My problem is that I cannot find fittings in bronze. Specifically, I need a tee with 1-1/4 hose barbs and a pipe-threaded branch connection. I have looked everywhere.
Look up Groco SSC-1250 if you haven’t already seen it. Not a T exactly, but functions the same.
 
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