Sea water cooling

[Andibs]

On my new to me boat, I have a Yanmar 2GM 20 inboard. Since buying the boat, the engine has only been used for getting in and out of harbour.

Yesterday however, I had to motor for 5 hours and noticed some white / grey exhaust coming from the outlet. Later inspection showed that the sea water filter reservoir was had no water in it. I had checked it was clear and full before settling off and when I tried the engine again, it was sucking some water up. Quick inspection and the connecting clips all seem tight and no apparent leaks.

Any ideas?

Cheers
Andy

 

[ianat182]

Have just replied to Gary Cottam's thread on a similar subject, maybe the same reasons; suggest you add a filter check after each use of the engine.

Ian

 

[Andibs]

Have just replied to Gary Cottam's thread on a similar subject, maybe the same reasons; suggest you add a filter check after each use of the engine.

Ian

Filter was clear, I checked it before and after

 

[pvb]

Filter was clear, I checked it before and after

If there's no water in it, it would suggest that air is leaking into it. Remove the lid, check/replace the O-ring, lubricate with silicone grease, replace.

 

[PetiteFleur]

It has an air leak - as pvb says, replace/silicon grease for the screw thread. I had to make a lever to tighten the thread sufficiently to make it air tight.

 

[Champagne Murphy]

Check the pipes into the seawater strainer. Sometimes they crack withage, especially where the hose clips grip.

 

[Andibs]

Many thanks for the advice folks, the grease sounds like a plan as I checked the O ring before settling off.

Cheers
Andy

 

[simonfraser]

Impeller will also pump better when greased.
It may sit away from the face plate possibly due to wear, which wont help either.

 

[Leonidas]

Are you sure that the seacock is not fouled up or accidentally closed? If this is ok, when did you last check the condition of the impeller of the cooling pump?

 

[pvb]

Are you sure that the seacock is not fouled up or accidentally closed? If this is ok, when did you last check the condition of the impeller of the cooling pump?

How would either of those conditions allow air to enter the filter?