Raw water strainer reccs for Detroit 671 TI's

[MV Aurai]

Hello fellow nautical masochists.

I have a pair of J&T 671 TIs in my Ocean Supersport. Weirdly (to me) neither raw water pickup is fitted with a seastrainer other than the slotted scoop skin fitting.

The pick-ups are 3" diameter that run from the seacock straight into the transmission oil cooler, then the Jabsco raw water pump and on to the Intercooler, engine heat exchanger, and so on. Having just spend buku bucks restoring the ICs and cleaning out all the accumulated organic junk, I'm turning now to prevention...

Looking for recommendations and advice from this group about whether this might be normal for these boats, and then if folks have 671T-I's I'd love to hear or see how are your strainers set up.

Thanks in advance.

Andrew
MV Aurai '77 Ocean SS 40

 

[Comodave]

Welcome aboard. Some boats don’t have strainers and only the slotted covers on the hull. Putting strainers in will probably not prevent the organic growth inside the cooling system. Strainers are designed to stop large particles of whatever from getting into the cooling system. To clean the system of the organic growth maybe look into a cleaner like Barnacle Buster. It will help clean the cooling system without having to take it all apart. It may not be able to clean out a completely clogged system but if you use it on a regular basis it may help prevent the growth from getting out of hand,

 

[MV Aurai]

Thanks!



Just to clarify, Aurai lives in the fresh and weekends in the salt, so I don't have "growth", just accumulated detritus sucked up and filtered out by the intercoolers and heat exchangers instead of in a strainer.

 

[Lepke]

You need strainers. If you ever get into sea grass, it will eat your impeller in seconds.

Best setup is dual strainers so you can switch running, but not cheap.
I have twin 671s with dual cast iron strainers from WWII with new baskets. Flow is to pump first. I don't think I've ever seen a DD that didn't go to the pump first.

 

[MV Aurai]

You need strainers. If you ever get into sea grass, it will eat your impeller in seconds.

Best setup is dual strainers so you can switch running, but not cheap.
I have twin 671s with dual cast iron strainers from WWII with new baskets. Flow is to pump first. I don't think I've ever seen a DD that didn't go to the pump first.

Thanks for the reply. I definitely agree. I've 'been there and done that' sucking up weed on previous boats and am a believer in redundancy.

I'd like to hear more about your setup. Do you have apart number for that beautiful hunk o' bra$$?

 

[Lepke]

Do you have apart number for that beautiful hunk o' bra$$?

I just grabbed the picture off Fisheries Supply, Seattle

https://www.fisheriessupply.com/browse?terms=dual strainers


My boat was built in 1942 with twin 850hp gas engines. The strainers are from that time. My DDs are naturals from 1947. Rebuilt 10 years ago for the first time. Unknown hours, but could track 30,000 plus hours. Old manual transmissions with air shifting and air throttle. I've owned many DDs, but prefer naturals for my private boats because they last forever and great economy. I cruise at 10 knots @ 1800 rpm (max continuous) but POs cruised at 2500. Also 2-14kw generators and watermaker. Boat use to make yearly round trips from Canada to Mexico at about 12 knots. Later it was a custom cruise boat and did harbor cruises in Vancouver. When I bought it, it hadn't run in 6 years.