Volvo D2-55 Continuing cooling saga

RichardS

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When I start mine with the strainer empty the jet of water from the inlet hits the inside of the lid. This entrains a lot of air into the flow of water and the mixture gets drawn down to the pump. Over a few minutes the ratio of air to water reduces until the strainer is full of water.
That's exactly what mine does although mine only has a small volume of air to entrap. I'm surprised that the flow rate is sufficient to blast its way up through a half full version of the OP's strainer and entrap even more air and drag it down the outlet but if yours can do that then it sounds as if low pumping rate might well be the OP's problem.

Richard
 

DJE

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Mine is a Volvo 2040 maybe it has a bigger sea water pump. But there is no comparison with the flow rate in the OP's video and mine.
 

RJJ

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I'm not sure how it could be full as the rate of water ingress will always equal the rate of egress. Even if you were to fill it by hand, the water would always have run down into the sea by the time you get the top screwed on tight. If it were level with or below sea level the it would be full but I don't believe that to be the normal placement.

Richard
Easily avoided: close the seacocks or ball valve, fill the strainer manually, maybe squeeze the hose to help any bubbles. Close the lid, then open the ball valve and you should be starting with a full strainer.

If when you open the valve the water drains away, then you know there's a problem with the lid or seal.
 

Beneteau381

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Easily avoided: close the seacocks or ball valve, fill the strainer manually, maybe squeeze the hose to help any bubbles. Close the lid, then open the ball valve and you should be starting with a full strainer.

If when you open the valve the water drains away, then you know there's a problem with the lid or seal.
Thats how I know mine is ok. It always stays full even with the sseacock open. It means my pump is sealing good as well. The other week I took the lid off to clean some weed out. As soon as I loosened the lid I could hear the hiss as the air entered past the O ring and the water level dropped.
 

asteven221

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Thats how I know mine is ok. It always stays full even with the sseacock open. It means my pump is sealing good as well. The other week I took the lid off to clean some weed out. As soon as I loosened the lid I could hear the hiss as the air entered past the O ring and the water level dropped.

Gteat advice. I actually had given that a gi prior to reading your posts and I an confirm it works a you both desvribe. I now have a solid stream of water running through the hoses and a full filter. Unfortunately despite what initially seem a very strong flow from the exhaust dis materialise into the smoke or steam vanishing even at a constant 1700rpm. Still I am ticking off the possibilities, so thanks again.
 

asteven221

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Arrgh, sorry for all the typos. My samsung phone keyboard and spell checker has a mind of its own. And it cant spell.
 

DJE

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Gteat advice. I actually had given that a gi prior to reading your posts and I an confirm it works a you both desvribe. I now have a solid stream of water running through the hoses and a full filter. Unfortunately despite what initially seem a very strong flow from the exhaust dis materialise into the smoke or steam vanishing even at a constant 1700rpm. Still I am ticking off the possibilities, so thanks again.
I would check the sea water pump impeller, exhaust elbow, and heat exchanger tube stack next.

Edit; your heat exchanger might be different to mine.
 
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