Air leak on raw water suction strainer

[R_p_ryan]

I have the cooling system apart in my 1978 Mainship and was farting around with the raw water hose. I decided I'd open the sea valve and blow into it, to see if there was any resistance from fouling on the intake screen under the water. To my surprise there was air blowing out where the lid of the sea strainer meets the body. This was just my breath so the pressure was low. But I could imagine this was a significant loss of raw suction

I cleaned the mating surfaces and o ring and now it's fine. Might be something to check in case of overheating or loss of raw water volume.

This is a plastic unit with clear lid and a center knob to fasten it down. Seems a better design would is multiple clamping forces around the mating edges.

 

[psneeld]

Foresaw sea strainer...seemed ok as I installed them after seeing them on a friends boat.

Now I wish I hadn't. Not because of not sealing...but they plug up easily and are hard to clean with the silly triangular center feed. The basket setup is great...but not how they are fed.

 

[jleonard]

My guess is that you'll see a slight reduction in engine temp now that it's sealed. I have seen this several times in the past on boats I have helped troubleshoot.

 

[O C Diver]

Had one of those on my genset when I bought the boat. Lid was cracked (probably from over tightening). Replaced it with a traditional bronze one.

Ted

 

[bayview]

With suction it may have sealed and not leaked.

 

[psneeld]

they work fine.... nice to be able to look in and see the basket and water flow...the unclogging is my issue...otherwise nice strainers.

 

[Brooksie]

they work fine.... nice to be able to look in and see the basket and water flow...the unclogging is my issue...otherwise nice strainers.

What he said. Mine's (Vetus) been installed for years, gasket hardened up years ago and made a new one of silicone, better than new.

 

[R_p_ryan]

With suction it may have sealed and not leaked.

True, considering the cover is about 8" in diameter, or about 48 square inches, and a suction of 1 psi would result in 48 pounds pulling it down. But I also think there's a plastic lip on the housing that stops the lid from compressing the gasket any more, and I had some sandy crud in there.