Sea Strainers

[DCMY #92]

It's pretty clear from the experiences here that external strainers get the job done as good or better than internal strainers. So, I'm going to switch over.

I see that Buck Algonquin makes two styles. One with a slide out screen and one with a surface mount screen. Those of you who have experience with these strainers - is one style preferred over the other?

 

[rsmith]

Eggs!

My boat with 671TIBs came with the external South Bay strainers.

I was talked into adding internal strainers because small mussels were found inside the raw water
gear coolers.
How they got through the external strainers is a total mystery.
The mussels in the gear cooler were approximately 1/4 inch long.

I gave the green light for the strainers, and I think it cost something like $3K.
(Im not exactly sure about the price, I could check, but I seem to remember 3in strainers costing around 1k each)

With the external and internal strainers I have not had to empty the internal ones.

However, my AC and genny have the slotted through hull and internal strainer.
They need constant attention depending on the water quality.
I have had to clear the slotted ones sometimes twice a day in some anchorages.

 

[seasalt]

Who has the best deal on either South Bay or Buck Algonquin now-a-days?

I want some on hand next time I haul.

 

[Vincentc]

I've been pondering the issue of external strainers and silt and concluded that the horizontal mounting of the internal strainers prevents silt from collecting in the internal strainers like it collected in the vertically mounted internal strainers on our old boat.

External strainers would prevent the internal ones from getting clogged with grass and save me the very difficult task of cleaning inaccessible internal strainers.

If I add the external strainers, what are the advantages or disadvantages of keeping the old internal ones in place?

Sea salt. You can look on http://www.groco.net/SVC-MAN-07/Sec5/PDF/EX-HULL.pdf for the correct perforated sea strainer model for your boat then shop it.

Regards

 

[Fanfare]

Maybe I am just lucky but I have been up and down the entire U.S. east coast, including Chesapeake and Delaware Bays, and I have never had a problem with clogged main engine strainers. I have the stock slotted external wedges on the bottom and the internal Groco big strainers in the engine rooms.

The only strainers I have trouble with is the Groco AC strainer which seems to get debris directed to it from the chines. Also plastic bags. My generator dotted-perforation strainer also escapes most everything except for overly enthusiastic bottom painters who slop on so much paint it obliterates its holes.

 

[chuckbullett@gmail.com]

You guys- This is a great thread. We've got our '78 53MY hauled for post purchase work right now and the wealth of information on this list is invaluable.

We ordered the Buck Algonquin Sea Scoops a few days ago. Also in the starboard engine room, beside the added space from removing the sea strainer basket assembly, we are gaining extra breathing room for fitting in the new exhaust y-collectors from having removed the galley maid poop pump for the VIP mid-ship head. It is mounted just outboard of the starboard engine's manifold at a 45-degree angle. What a bugger to get to!

We've been advised to construct the new Y-Collectors for the 8V71T's exhaust out of fiberglass pipe so are doing do. I am also plumbing the exhaust elbows for fresh water flush at shutdown. Has anyone on the group here gone down that path? (Probably another thread... right?)

Other work going on now:

1. Galley appliances hauled out and off to the dumpster.Shopping for new and getting frustrated. Pepe' the woodworker is set to start installing new granite countertops and the appliances in a few weeks. Will also do granite tops on the bars on the sundeck.

2. New Heads being ordered... all new head plumbing on the way... ripping out the old hoses and heads today and tomorrow. The amount of abandoned hoses, and infrastructure hardware that was never removed is astounding. I can't wait to see where the water line will be when we get back in the water. We keep asking the yard to bring the fork lift up to the sun deck so we can push another load out.

3. All new thru-hulls. Glassing over five and abandoning them... for a total of 6 new thru-hulls.

4. Bottom will be faired after were done with the new thru-Hulls... currently sanded down and stripped. Bottom paint was delivered on Friday. Tropicoat with Bio- Boost

5. Ordered new batteries last month... should be coming in this week. Keeping the 32V systems in-place, so ordered eight new 8V batteres from Powerstride in New Jersey. I guess they build to order these days. I was told that they do not really stock them. Battery vendor will install a watering system for us.

6. Naid Stablizers. I've pulled the stabinzer fins and am orderering all new seals. The fins themselves are being encapsulated with about 6 layers of glass cloth and resin to stregthen them. Will wire brush the frames holding the rams and quandrants and paint them, plus paint the engine room floors and engines.

7. Bildge Cleaning! Seems like an every day thing while we're on the hard.

8. Pulled the starboard galley window, welding a new piece on to the bottom as electrolysis got the best of it.

9. James the Jamican is refinishing all of the tiger mahogany for us.

Tidying up all of the wire bundles... putting the new head plumbing and assosciated electrical into CAD, plus verying all of the wire numbers and capturing the wire inventory in spreadsheets is also part of the fun.

I found a bunch wet wood in the aft and mid ship showers today... doing a chin scratch on that one.

Thanks again all for your wealth and breadth of experience on all of these maintenance items. We're exhausted but know the results will be worth it.

Chuck & Lisa.
MV Chartmaker

 

[bigbill]

i think i am going to change to the south bay strainers when i haul in a couple of months. is everybody still happy with theirs? does anybody know what size i would use on a 58 yachtfish for the engines and the a/c's ?

 

[Tim Powell]

Thanks to you all!
From memory these are the external strainers I have. Going through all the photos I have of the last haul out to confirm and will dive under the boat when I get the chance. I have never seen them in Australia before, hence the question.
Cheers.

I took my factory installed sea strainers out this past year. Both engines were running at a point where if anything went wrong it would heat after installation of the external strainers the boat ran dead on 170 degrees. I did it because of the eel grass at Hatters its tourable and the sea strainers love it.

 

[Tinman]

The worst problem I ever had with slotted strainers was jelly fish at the Pelican in Ft. Pierce. External perorated strainers definitely the best. Thinking of changing over the Gen and A/C's next haulout because of eel grass around the bay.

 

[saltshaker]

i think i am going to change to the south bay strainers when i haul in a couple of months. is everybody still happy with theirs? does anybody know what size i would use on a 58 yachtfish for the engines and the a/c's ?

I had them for 13 years on my 46C and never had to touch them. Just make sure the holes don't get loaded up with paint and your good. We get tons of jellyfish for a few weeks when the water gets hot. Most boats that don't have the external strainers get the AC intakes clogged a few times a day. After I added the externals I never had a single clog.

 

[bigbill]

i am getting ready to haul out next month and i want to have these strainers on hand. does anybody know what size or a model number that i would use on a 58 yachtfish??

 

[Diver Down]

BigBill, we installed Algonquin external strainers over our engine thru hulls, p/n 00rss1000p. Bought these from Deep Blue Yacht Supply.

 

[sandspur1966]

On the 70 footer I run, I put an external strainer on the watermaker about 4 years ago as a test. The year before, in Nantucket, the strainer had to be clean almost daily because of grass. The external strainer solved that issue 100%

Two years ago at the next haul out, I had them installed on the 3 air con intakes and again, no more strainer cleaning...

As mentioned above, you have to be careful installing them on generator intakes as the scoop could force water up the exhaust of the generator at speed. May not be an issue for single genset boats where the Genset runs at all time but it could be if you have two gensets. I considering switching the intake on our next haul out but will drill holes in the back to make sure there is no pressure up the exhaust.

I solved this problem with a groco electric seacock on the through hull. It is wired into the ignition circuit so when the generator is on, the seacock opens and vice versa, is closed whenever the generator is off.

I considered doing the same for the mains but the cost for the larger version of the electric seacocks was too high to justify this little gimcrack.