I really like the idea of using the newer plastic sea strainers you see being used increasingly on new boats. They offer one less thing to get green with corrosion and nearly impossible to open up to clean out once they get that way. But I have observed something about them that needs to be shared with all of you that may have one of these installed on your boat. The strainer I'm talking about is shown in the photo below to the left of the engine as you look at it.



The caps on these units simply thread onto the reservoir. But, that's the catch. Having taken a few of these apart to clean out the strainer of debris I've observed that it is extremely easy to cross thread the cap when reinstalling it. Be Careful! I was amazed at how easily this can happen. If you get it cross threaded and then force screw the cap down either it won't seal or you may actually crack the cap. Either way you'll have a problem. Don't expect to be able to find a new cap at the next boatyard you pull into because you won't.


When servicing these strainers make certain that the strainer basket is in its proper resting place within the plastic housing and carefully rethread the cap back. It should screw on easily with no force needed. If you encounter any resistance in threading the cap on, STOP! Back the cap off and start over making sure the threads on the cap and housing are properly engaged. A close up look at one of these units made by Vetus is shown here:



With a little caution these strainers should last several lifetimes, just watch those threads!

Written by: Ed Sherman
Ed Sherman is a regular contributor to boats.com, as well as to Professional Boatbuilder and Cruising World, where he previously was electronics editor. He also is the curriculum director for the American Boat and Yacht Council. Previously, Ed was chairman of the Marine Technology Department at the New England Institute of Technology. Ed’s blog posts appear courtesy of his website, EdsBoatTips.