Thru hull external strainer

NYSail

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Jan 6, 2006
3,048
Beneteau 423 Mt. Sinai, NY
So I am continuing my replacement of a few they hull fittings and seacocks. My engine has an external strainer....... what are the feelings of these. All previous boats did not have these and I see limited amounts in yard.

Thanks
Greg

image.jpg
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
There's a recent thread on this. Might help.
 
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Tom J

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Sep 30, 2008
2,301
Catalina 310 Quincy, MA
I've never had an external strainer. A friend had them on his power cruiser, and we had to shut down one engine when it overheated due to barnacles on the external strainer. That being said, I had to repeatedly shut down my engine and clean the internal strainer one day while motoring across Florida Bay, when sea grass kept blocking water flow. At least I could get at my strainer without diving.
 
Feb 10, 2004
3,917
Hunter 40.5 Warwick, RI
I've never had an external strainer. A friend had them on his power cruiser, and we had to shut down one engine when it overheated due to barnacles on the external strainer. That being said, I had to repeatedly shut down my engine and clean the internal strainer one day while motoring across Florida Bay, when sea grass kept blocking water flow. At least I could get at my strainer without diving.
Everybody has their own experiences. Like you, Tony, I had frequent grass clogs in my internal Groco strainers for both my engine and genset. More for the genset- I think it was because I was not moving and anything that happened to float by got sucked in.

I would never install the one-piece strainer and thru-hull like the OP's picture shows because it is too hard to clean out. In fact I removed onefor my A/C intake. In post #2 above, a previous thread was referenced and in that thread I have pictures of my hinged-cover external strainers. Since installing those strainers with holes, not slots, my internal strainer receives almost nothing. I literally clean my internal strainer once per season and only take out a couple short pieces of grass.

So the bottom line is that not all external strainers are equal. As Stu likes to say, "Your boat, your choice".
 
Aug 18, 2020
10
Pearson 31-2 Harraseeket River S. Freeport
I love ours! We're in Maine and have only had our boat for 2 seasons but use it a lot.. The first season we were constantly plugging the raw water intake with weeds. On 2 occasions I had to go in the water to clear them. I installed the groco RSC strainer (hinged with round holes) at the beginning of this past season and never had any clogs. I painted it with bottom paint and there was no growth on it at all. Find it here: Round Bronze Hull Strainer | GROCO
 

NYSail

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Jan 6, 2006
3,048
Beneteau 423 Mt. Sinai, NY
I have never had an issue with my engine intake clogging..... however at the end of every season clean all sorts of mussels and barnacles out from inside the strainer. Also as Maine says it’s easy to clean from the inside. On my ac intake it will clog after a couple of days as we are not moving.... this fitting has no external strainer. I take the hose off holding it above water line, use my dinghy pump and blow it clean. So think I will stick with my first thought and trade for no external strainer.... thanks!

Greg
 
Feb 2, 2010
373
Island Packet 37 Hull #2 Harpswell Me
I fitted the hinged version of the Grocco strainer and it was probably the best improvement i ever made. I was forever clearing the internal strainer or getting clogged up, i have never once had a problem since fitting. Sea grass in my Maine mooring field is the problem.
 
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RoyS

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Jun 3, 2012
1,739
Hunter 33 Steamboat Wharf, Hull, MA
I use both external and internal strainers. The external keeps out the jellyfish and the internal collects the seagrass. I have tried all arrangements with external, internal and no strainer combinations and ended up with both as the best for me. As long as you pay attention to these items on annual haul-out you should have no problems at all.
 
Jul 5, 2011
702
Oday 28 Madison, CT
South Bay Strainer (Cheese wedge style, external, small holes) - 30 years never a worry, never a clog. Don't paint the pinholes closed is all.....