Raw water strainers: Plastic, bronze or both?

[Christian Van H]

Hi All! I'm about to order my raw water stainer, which will be mounted slightly below the waterline. I've been told to stay away from all plastic units such as the Raritan (because of my below the waterline mounting). Are combination bronze units with plastic bowls safe? I also like the Buck Algonquin unit... Any thoughts?

[Pblais]

Are combination bronze units with plastic bowls safe? I also like the Buck Algonquin unit... Any thoughts?

I'm not so sure I would categorically eliminate all plastic strainers. Many of the Gorco strainers use plastic components in their strainers but I think they are well made.

We use a Vetus raw water strainer that is "plastic" not sure of the type but it is located above the water line. It may be possible to use one and raise the level of the strainer. Nothing requires the strainer to be below the water line. I would agree if you are below the waterline it would not be a good choice.



The bronze below the water line are still very popular and would be a good choice.

[David M]

I would feel a little nervous about having a plastic strainer below the waterline. Strainers are probably one of those places where one should not cut corners in order to save money. I think sticking with time proven designs and materials is worth the piece of mind it provides.

[Jmolan]

We used plastic on many things in the big boat for years in the engine room untill the insurance guys came along and put a stop to it. I guess the only thing that would concern me (and them) is a fire situation, where you may suddenly be fighting more than a fire....:-)

[Christian Van H]

Originally Posted by Jmolan

I guess the only thing that would concern me (and them) is a fire situation, where you may suddenly be fighting more than a fire....:-)

Good point! I guess one would win eventually!

[AnchorageGuy]

If you have a fire in the engine compartment the hoses are going to melt so if the strainer is plastic what difference does it make? We have used/installed Groco strainers for years with plastic and never had an issue or a surveyor or insurance issue. What "insurance guy" put a stop to plastic in the engine compartment. If your boat is fiberglass it is surrounded with plastic, OK technically not, but you get my point. Rubber fuel and water hoses will melt so what does insurance say about that?

[cat man do]

I like the benefits a lot of the plastic ones have as well, like the entire lid being clear plastic for easy inspection.

Being a fraction of the price is good as well

Whitworths Marine: Raw Water Intake Strainers - 40mm Hose

These are very similar to what I have

[AnchorageGuy]

The Groco are still mostly bronze with a plastic basket. Many of the new boat builders are putting all plastic strainers on their new $750,000.00 boats so not sure why someone would come in and say that is a safety hazard.

[Jmolan]

Originally Posted by Chuck Baier

If you have a fire in the engine compartment the hoses are going to melt so if the strainer is plastic what difference does it make? We have used/installed Groco strainers for years with plastic and never had an issue or a surveyor or insurance issue. What "insurance guy" put a stop to plastic in the engine compartment. If your boat is fiberglass it is surrounded with plastic, OK technically not, but you get my point. Rubber fuel and water hoses will melt so what does insurance say about that?

Chuck. It was Lloyds....it's big boat stuff, I may be off base here.

The boat I am referring to is a 125' offshore Bearing Sea trawler. The plastic I was referring to is 6" sced. 80 PVC we were using for seawater recirculation for refrigeration of 500,000 lbs. of fish. To melt that would cause a big leak...:-) We also installed manual remote wire shut offs to the fuel supply the Eng. room for the same reason. There is no rubber hoses in the Eng. room. All 3 aux. and main engine are steel piping. We deal with 3K psi Hydraulic pressures along with a lot of other nasty stuff that can cause fires.
Anyhow, different boats need different solutions.

This is a pic of us in a haul back. The is 150 tons coming up the ramp. (All of it is done with synthetics by the way) but no thread drift

[AnchorageGuy]

You won't find too many folks here with those kinds of set up or issues so it probably really does not apply to the original question.

[Christian Van H]

Naw, but it was a cool picture! Thanks, Chris

[Pblais]

I think the material "Plastic" has a lot of variations. Gorco uses lexan components in it's below the water line strainers and they really are very solid gear. They have a nice one with an integrated seacock as well. being able to see inside the strainer is a plus.

[David M]

The Coasties require metal thru-hull valves on Subchapter-T vessels. The theory is that plastic valves would melt in a fire.

On an aluminum hull, I had to thread stainless steel valves onto aluminum pipe nipples. The electrolysis would eat up the aluminum threads in about two to three years if ignored. It did not matter that a corroded pipe nipple had a greater chance of sinking a boat than a melted plastic valve.

[AnchorageGuy]

David, you are correct but this does not apply to pleasure vessels such as Christian's which ask the original question. We are not discussion commercial vessels, at least I did not think so. To my knowledge the Coast Guard does not inspect pleasure vessels for these kinds of issues.

[David M]

I realize that. I just thought I would throw in that little story.