External Strainer install

[Irie308]

Planning on installing this external strainer on our generator. My concerns are am I going to make my situation worse. Doesn't happen every year but every now and then we get seagrass, seaweed etc in the anchorages that clogs the gen. Its about a 1" pickup with the strainer basket inside the bilge. I do have it down to a science where I can clear it from in the boat. In extreme cases I have to remove the hose and hook up my dinghy air pump and blast some air through the hose to fully clear it. If its really clogged I have to remove the entire hose. My worry is if seagrass gets past the holes in the strainer then I'm diving in. More of a hassle. Anyone else using this type of strainer and does it allow anything past the holes? Second concern is growth slowly clogging it over the summer. Thoughts?

https://www.amazon.com/gp/product/B000208DUW?ref=ppx_pt2_dt_b_prod_image

 

[Richard Carlisle]

The upside on an external strainer is that unless it’s really clogged, you should be able to shut down the genset and let the water flow past the strainer clear it out. The down side is that if it gets really clogged, you are diving.

I have sucked up junk a few times and didn’t have any trouble cleaning out the internal strainer. I figure that’s less of a hassle than donning the dive gear.

The question is….would the junk I sucked up be dealt with by the external strainer without clogging? Don’t know, it given the ease of cleaning the internal strainer, I decided against external strainers.

 

[Jeremygavin]

I have been thinking about something like this as well, but I hesitate to do it for all the reasons you mentioned. I was thinking maybe a better cure is too enlarged the thru hull to 1 1/2” hose and get a larger strainer with 1 1/2” inlet so that it can handle larger quantities of seagrass and my theory is the seagrass will not get stuck in the hose from the thru hull to the strainer. Thoughts?

 

[ttmott]

We get a lot of sea grass a couple of times a year and I've plugged up that thru-hull several times.
Two times there was whisps of steam in the gen exhaust and one time it actually shut down on overtemp.
All three times I had to dive the boat and pull the wad from the hole and also pull the hose from the strainer and ram a fiberglass rod down to push out the remainder. One thing that worries me is if the gen isn't running and I have a screen on the hull will the forward motion of the boat push water up and through the generator. That would be really bad. One screen they sell is shaped like a wedge. The one you show is a first for me.

 

[Skybolt]

Planning on installing this external strainer on our generator. My concerns are am I going to make my situation worse. Doesn't happen every year but every now and then we get seagrass, seaweed etc in the anchorages that clogs the gen. Its about a 1" pickup with the strainer basket inside the bilge. I do have it down to a science where I can clear it from in the boat. In extreme cases I have to remove the hose and hook up my dinghy air pump and blast some air through the hose to fully clear it. If its really clogged I have to remove the entire hose. My worry is if seagrass gets past the holes in the strainer then I'm diving in. More of a hassle. Anyone else using this type of strainer and does it allow anything past the holes? Second concern is growth slowly clogging it over the summer. Thoughts?

https://www.amazon.com/gp/product/B000208DUW?ref=ppx_pt2_dt_b_prod_image

I have that same type on mine. Works great, but I also put a back flush (SS t and valve) in because of jelly fish getting stuck. Works great and I never have any problems with the strainer now.

EDIT: I also have south bay strainers on the engines. Like the Oceans do, I am now considering taking out the internal strainers as they never need to be cleaned.

The only menace is the AC strainer ...

 

[Jaybeaux]

Would it just be easier to install a larger strainer, like on the mains, to give more capacity to strain out sea grass, etc? Just thinking outside of the box.

Jaybeaux

 

[Skybolt]

Would it just be easier to install a larger strainer, like on the mains, to give more capacity to strain out sea grass, etc? Just thinking outside of the box.

Jaybeaux

Newer Vikings and all Ocean's don't even have strainers installed. They use the South Bay strainers external to the hull.

 

[Irie308]

I have been thinking about something like this as well, but I hesitate to do it for all the reasons you mentioned. I was thinking maybe a better cure is too enlarged the thru hull to 1 1/2” hose and get a larger strainer with 1 1/2” inlet so that it can handle larger quantities of seagrass and my theory is the seagrass will not get stuck in the hose from the thru hull to the strainer. Thoughts?

Jeremy, thought of this as well since most times the hose gets the majority of the clog. The basket is never clogged to the point it’s jammed up. But wondering if it would just prolong the window between clogs and the hose would still be the bottle neck.

 

[Irie308]

Would it just be easier to install a larger strainer, like on the mains, to give more capacity to strain out sea grass, etc? Just thinking outside of the box.

Jaybeaux

The hose would still be the choke point.

 

[Irie308]

We get a lot of sea grass a couple of times a year and I've plugged up that thru-hull several times.
Two times there was whisps of steam in the gen exhaust and one time it actually shut down on overtemp.
All three times I had to dive the boat and pull the wad from the hole and also pull the hose from the strainer and ram a fiberglass rod down to push out the remainder. One thing that worries me is if the gen isn't running and I have a screen on the hull will the forward motion of the boat push water up and through the generator. That would be really bad. One screen they sell is shaped like a wedge. The one you show is a first for me.

That’s why I chose this one. It’s designed not to force water up the thru hull. I had a friend that installed it on his prestige last season. No issue with forcing water in and he didn’t encounter any clogging issues either. However don’t think he anchored out as much last season.

 

[ttmott]

Newer Vikings and all Ocean's don't even have strainers installed. They use the South Bay strainers external to the hull.

The South Bay are a scoop style of strainer. You wouldn't want that for a generator's raw water side; that is, unless you like milkshakes.

 

[Jeremygavin]

Jeremy, thought of this as well since most times the hose gets the majority of the clog. The basket is never clogged to the point it’s jammed up. But wondering if it would just prolong the window between clogs and the hose would still be the bottle neck.

I agree that it might just prolong it but maybe that would get me through a night or day. I was also thinking the larger hose might let the seaweed make it to the strainer instead of clogging the hose.
I have the most issues on the moorings at Edgartown as a lot of seaweed come through the harbor from Katama bay when the tide goes out.

 

[b_arrington]

Second concern is growth slowly clogging it over the summer. Thoughts?

https://www.amazon.com/gp/product/B000208DUW?ref=ppx_pt2_dt_b_prod_image

Slow growth really isn't an issue so long as you apply some antifouling. The type you linked to opens so it would be super easy to spray on both sides, plus on the through hull itself.

I boat in a heavy fouling area and have not had mid-season issues with growth over these type of external strainers when some spray antifouling is applied.

 

[Richard Carlisle]

You guys have me considering external strainers again on the mains and ditching the Groco’s. Local yard has some Buck Algonquin. Is there any reason to choose South Bay over these?

 

[Skybolt]

The South Bay are a scoop style of strainer. You wouldn't want that for a generator's raw water side; that is, unless you like milkshakes.

My generator has the round hole type made by Perko, pic below, and the main engine(s) have the South Bay(s) on them already. So no milk shakes! But to your point, yes, they are a wedge shape. Actually helps the raw water flow and cooling. I actually think they are Buck Algonquin because they have the slide out replaceable screen and not the multi screw on version.