Hydromatic® Self-Cleaning Strainers

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drmnj

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Does anyone out there have any experience with the Groco Hydromatic® Self-Cleaning Raw Water Strainers?
 
Does anyone out there have any experience with the Groco Hydromatic® Self-Cleaning Raw Water Strainers?

No. Had to look them up to see what they were.

Hoo, boy! Talk about boat bucks!
 
I'm looking at these since we have a grass problem in our marina that requires weekly cleaning of the strainer. We travel for work a lot and can't keep up the schedule of weekly cleanings. It is serious boat bucks but I think it's going to be worth it. Once we make the leap I will report back on how well it works.
 
Wow. Don't envy you. I think I would move my boat before going to $2500 for a single strainer!
 
Could you trust it ? or is it just another potential problem waiting to happen .
It takes me 3 minutes to check my strainers while Im doing my other checks so I dont see where it would benefit me in any way apart from making me lazy
 
I use the Buck Algonquin external strainer with the slide in screen. Grass and seaweed just slide over the screen. The larger the size you use, the less suction per hole in the screen. Chesapeake Bay grass just slides on by.

Ted
 
I had one. Put in on a 48ft sportfish back in 2002 when they first came out. I was located on the Mississippi gulf coast. It was a little time consuming to install because of the high amp draw. It had a plastic strainer basket. It never stayed any cleaner than the standard strainer basket I had. It was for for AC. After 6 months, the seal in the bottom went bad and filled the motor with salt water. The plastic basket came apart. I drill out the bottom and plugged the hole, made a SS basket and had a VERY expensive raw water strainer. Maybe they have gotten better, good luck
 
I had one. Put in on a 48ft sportfish back in 2002 when they first came out. I was located on the Mississippi gulf coast. It was a little time consuming to install because of the high amp draw. It had a plastic strainer basket. It never stayed any cleaner than the standard strainer basket I had. It was for for AC. After 6 months, the seal in the bottom went bad and filled the motor with salt water. The plastic basket came apart. I drill out the bottom and plugged the hole, made a SS basket and had a VERY expensive raw water strainer. Maybe they have gotten better, good luck
That's not what I wanted to here. We're gone sometimes 6 weeks at a time working in whatever state calls us. We we're hoping being Groco it would be a reliable product. I'll research their warranty a bit more.
I'll look at the Buck Algonquin and see if that would work with our hull and grass.
 
Let's look at this another way, do you run your A/C continuously while you are away from the boat for extended periods? If yes, why?

I keep my boat in Stuart, so pretty similar conditions, and I went away from running the A/C all the time quite a few years ago. The secret is to focus on reducing humidity, don't worry so much about temp. I use two little EvaDry dehumidifiers, they run 24/7, one sits in the sink in the head, the other in the galley sink. I drilled a 1/4" hole in each of their tanks, so they drain into the sink which drains overboard. I learned this trick from others on the forum. It works great, no mold or other issues in my boat at all. Ever.

My brother has a 40' Ocean in Fort Myers, he used to run his A/C all the time. Tons of issues with clogged strainers, burned out supply pumps etc. He switched to this method a few years back as well, and has had no more problems.

Saves a lot of wear on your A/C system. Also eliminates a source of water being pumped into the boat non stop while you are gone.

Give it a try. I think you will be happy with the results.
 
Sounds like a less expensive "worth a try". I give that a shot. Should save on the $200+ a month electric bill we have this time of year. Thanks
 
I use two little EvaDry dehumidifiers, they run 24/7, one sits in the sink in the head, the other in the galley sink. I drilled a 1/4" hole in each of their tanks, so they drain into the sink which drains overboard. I learned this trick from others on the forum. It works great, no mold or other issues in my boat at all. Ever.

Which model EvaDry are you using? I see a little bit of a range in them. I think that at some point (size) heat starts to become a factor. I have a larger GE unit that I used. Once. Got onboard after a few hours of running and the thing had heated the boat up to 100 degrees.
 
https://www.groco.net/products/raw-water-strainers/self-cleaning/970-series

Scroll down the linked page... See Diagram... Notice "Hull Strainer" on diagram's bottom right.

Well... here's my story and outlook:

Story - Starting in 1950's; I was very often aboard dad's boats since then I've owned my own boats. I also worked in boat yards when in my teens on other peoples' boats.

One [1] of my boats with twins had internal filter baskets with glass tops. They did their jobs... they stropped [i.e. filled with] small pieces of debris [sea plant life that the Hull Strainer had let through] until they needed to be cleaned out so the filter basket didn't fill enough to restrict flow. Can only imagine that if I had let them fill too full - engine would overheat... I guess.

Outlook: Since all other boats [besides the one mentioned above] I've been intimately associated with had only Hull Strainers with no clogging that overheated an engine, and as far as I know let nothing through to ruin impellers... I prefer Hull Strainers only.

Note: One time while anchored a gen set's Hull Strainer did get covered with plant life sucked tight against its grating. Generator began to overhead. Shut it down in time and cleared plant debris under boat the next day. A filter basket would not have stopped that circumstance.

The GROCO 970 Series Hydromatic strainers macerated discharge should remove the need for cleaning any filter baskets... but... what if the maceration feature fails? What then... if the raw water system becomes too clogged?? And, at a cost of $2.5K +/-. Well... using only under water Hull Strainers is my preferred way to go!
 
Which model EvaDry are you using? I see a little bit of a range in them. I think that at some point (size) heat starts to become a factor. I have a larger GE unit that I used. Once. Got onboard after a few hours of running and the thing had heated the boat up to 100 degrees.

I have two of these: https://www.amazon.com/dp/B000H0ZDD...t=&hvlocphy=9011587&hvtargid=pla-305170695489

They don't put out any noticeable heat. I let them run 24/7 as long as I am plugged in, even when I am on the boat. I've noticed a big, big drop in the amount of mold and mildew in the cabin. I basically don't see any at all anymore. People often comment on how good our boat smells when they get onboard as well. Great little units.
 
Sounds like a less expensive "worth a try". I give that a shot. Should save on the $200+ a month electric bill we have this time of year. Thanks

Yep, that too. They use very little power.

My boat is generally around 88 degrees when I get on board on a hot summer day. But it cools down quick and doesn't seem to hurt anything.
 
I agree with you completely that exterior strainers are better then basket strainers at least for main engines. In addition, external strainers with trap doors are even better. Removable screens and access to clean inside the strainer and thru-hull opening (see attached).

Something else I have noted over the years I have not seen mentioned in this thread yet. Scoop type strainers seem to catch marine larvae that attach inside and then grow up. I have seen many instances of large clams, oysters and crabs inside scoop type strainers. Have yet to see that in a screen type strainer.

https://www.groco.net/products/raw-water-strainers/self-cleaning/970-series

Scroll down the linked page... See Diagram... Notice "Hull Strainer" on diagram's bottom right.

Well... here's my story and outlook:

Story - Starting in 1950's; I was very often aboard dad's boats since then I've owned my own boats. I also worked in boat yards when in my teens on other peoples' boats.

One [1] of my boats with twins had internal filter baskets with glass tops. They did their jobs... they stropped [i.e. filled with] small pieces of debris [sea plant life that the Hull Strainer had let through] until they needed to be cleaned out so the filter basket didn't fill enough to restrict flow. Can only imagine that if I had let them fill too full - engine would overheat... I guess.

Outlook: Since all other boats [besides the one mentioned above] I've been intimately associated with had only Hull Strainers with no clogging that overheated an engine, and as far as I know let nothing through to ruin impellers... I prefer Hull Strainers only.

Note: One time while anchored a gen set's Hull Strainer did get covered with plant life sucked tight against its grating. Generator began to overhead. Shut it down in time and cleared plant debris under boat the next day. A filter basket would not have stopped that circumstance.

The GROCO 970 Series Hydromatic strainers macerated discharge should remove the need for cleaning any filter baskets... but... what if the maceration feature fails? What then... if the raw water system becomes too clogged?? And, at a cost of $2.5K +/-. Well... using only under water Hull Strainers is my preferred way to go!
 

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  • Groco hull strainers.pdf
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I agree with you completely that exterior strainers are better then basket strainers at least for main engines. In addition, external strainers with trap doors are even better. Removable screens and access to clean inside the strainer and thru-hull opening (see attached).

Something else I have noted over the years I have not seen mentioned in this thread yet. Scoop type strainers seem to catch marine larvae that attach inside and then grow up. I have seen many instances of large clams, oysters and crabs inside scoop type strainers. Have yet to see that in a screen type strainer.

pdf.gif
Groco hull strainers.pdf (485.4 KB, 2 views)

Thanks for link.

Our Tolly has:

- Similar grating to SC Series with no mounting ring for twins

- Similar to RSC Series for gen set with no hinged portion.

- 1" i.d. open holes for each of both toilets

Each time we boat, except in the coldest mid winter months, I swim under boat with flashlight, knife, awl and bronze bristled BBQ brush that has scraper blade making sure each intake is not becoming clogged and remains in good condition.

Each time while going under [by holding breath only] I also scrape clean the anodes as well as shafts, struts. rudders... etc. We boat in SF Delta fresh water so any type of growth is minimal.


Going under while anchored to keep things clean is one of my favorite pass times. Great exercise for my lungs. Keeps me close in touch with my Gal's "Bottom"... Oh La La! :D :thumb:
 
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I think dehumidifiers work well on most trawler type vessels because the interiors are good quality wood and trims are mechanically fastened. Boats that have a lot of glued on upholstery and certain types of laminates may suffer if left hot too much. Heat can crack thick clear coatings (not varnish or lacquer) and undo adhesives.

Yep, that too. They use very little power.

My boat is generally around 88 degrees when I get on board on a hot summer day. But it cools down quick and doesn't seem to hurt anything.
 
Let's look at this another way, do you run your A/C continuously while you are away from the boat for extended periods? If yes, why?

I keep my boat in Stuart, so pretty similar conditions, and I went away from running the A/C all the time quite a few years ago. The secret is to focus on reducing humidity, don't worry so much about temp. I use two little EvaDry dehumidifiers, they run 24/7, one sits in the sink in the head, the other in the galley sink. I drilled a 1/4" hole in each of their tanks, so they drain into the sink which drains overboard. I learned this trick from others on the forum. It works great, no mold or other issues in my boat at all. Ever.

Saves a lot of wear on your A/C system. Also eliminates a source of water being pumped into the boat non stop while you are gone.

Give it a try. I think you will be happy with the results.

:thumb: +1 here. I use the Eva-Dry 2200 on my 34 and have been very pleased with the results.
 
Thanks Doug and FlyWright. 2200's it is. Have read good things about them elsewhere as well. With a GB 42' I think I will put one in the galley/salon and one in aft stateroom head. I don't have any mold/mildew issues but want to keep it that way. Plus I do hear that they help with that old musty boat smell and I do have a bit of that. I do wonder if one would be enough though instead of two.
 
Some ears ago I put a Groco APHS strainer on the outside of the hull. I didn't remove my inside strainer but I don't think I ever had to clean it again. The Groco APHS has a trap door that opens so you can clean out the thru-hull if critters grow in it.

I had a terrible problem with mildew until I started using an Eva Dry dehumidifier.
I rigged it to drain into the galley sink and I put a hydrometer in the cabin. The Eva Dry dropped the humidity to just over 60%. No more mildew. If one Eva Dry doesn't drop the humidity enough, use two.
 
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