bertram31.com

Hello All-

I took Captain Patrick's advice this winter and removed my internal sea strainers---it's nice to be able to see my sea cock again after all these years (no jokes please)! The old internal sea strainers were massive, its hard to see how they fit where they did and I suspect they were oversize for my engines.

I'm stuck--Captain Patrick didn't specify in his instructions what size replacement Groco sea strainers to use and the APH-2000-3 (5.5" x 4.0" screen area) I bought look like they have much lower capacity than the ones they are replacing. Can anyone who uses external sea strainers offer advice on sizing the Groco's or tell me what has been working for them? I'm running Yanmar 315's in Amberjack.

Thanks All,

This was Pats recommendation:

In terms of raw water sizing, always go one size larger than the engine fitting for the through hull fitting, and 1 size larger for the strainer. ie: Engine raw water pump fitting = 1.5"; through hull should be 2" for standard or 1.5" full flow; strainer size should be 3". This give you a margin of safety in case some of the openings in the strainer get clogged between bottom jobs. Reduce the oversized hose just before the raw water pump, not at the through hull fitting.

Most diesel engines that will fit a B31 will be either 1.5" or 2" raw water fittings.

I had asked Capt pat a while back and he told me to go with the 3" and that's what I did...
I agree with Mike...

John--

By 3" do you mean the Groco APH-3000 model which is sized for 3" through hulls? I would upsize in a heartbeat as Mike recommends but I want to use the same size sea strainer Captain Patrick used in order to get the same results. The different sizes will toe in at different angles using his positioning technique.

The Groco recommendation for our size through hulls (1.5-2.0") is APH-2000. It sounds as though Captain Pat upsized the sea strainer to APH-3000 (3.0" through hulls).

I have the 2000 model with cummins 210s and so far so good 1 1/4 inch full flow through hulls

If the 315's require a 2" through hull (and I believe they do) go with the 3" strainers.

Sorry for the delay, I used the aph-3000 model toed them into the centerline of the hull same as Capt Pat advised me to do. My intakes are 2" I'm glad I listened... the 2000's didn't look like enough...

LOL... For me only the APHS-6000 was suitable...

(The joys of owning a bigger Berty... Everything is bigger... And therefore more $$$)

Thanks everyone for the input. I went with the 3" version (APH-3000) and I'll post before and after pictures when the project is done.