Excess Steam / Anti-siphon valve

[rdempsey]

My "new" boat seems to have excess steam coming from the exhaust. Would this mean it is running too hot? The heat exchanger is topped up. What should be checked? I was thinking the raw water impeller, intake and filter.
Engine is a Yanmar 2GM20F.
It runs smooth with no power loss.

Also, there does not seem to be an anti-siphon valve. The engine was rebuilt 50 hours ago because of an "exhaust problem where water got in the engine".
Am I going to have the same problem? Am including a pic of the exhaust.

[delmarrey]

In the picture, the short hose on the left side, is that your exhaust cooling line????

If so, It's on the wrong side. It should be on the downward side and not the upward side. If it was like that before the rebuild that could how the water got in the motor. The cooling line is suppose to cool the exhaust outlet, only. Water spraying into the direct heat would cause steam.

Another thing too! There should not be a rubber hose so close to the outlet like on the right side. There should be more metal (to be cooled) leading down to an oulet tube. It looks like a bad set up to me!

As for a riser, that depends on where the motor is in relation to the waterline.

[rdempsey]

Originally Posted by delmarrey

In the picture, the short hose on the left side, is that your exhaust cooling line????

The short hose is raw water going from the heat exchanger on the left, to the exhaust elbow.
It looks like the elbow is on backwards doesn't it?

[delmarrey]

Originally Posted by rdempsey

The short hose is raw water going from the heat exchanger on the left, to the exhaust elbow.
It looks like the elbow is on backwards doesn't it?

Yes! I think I would replace the whole unite!

This is a bad example but the cooling is set up properly and worked for 25 years.

[delmarrey]

This is how it is set up now.

[S/V Antares]

The elbow is a jacketed exhaust. The water actually exits on the downard side to the right. They are notorious for getting clogged or restricted. Then the lack of flow causes steam. You should have an antisiphon valve installed asap and remove and inspect the elbow. If it is more than 5 years old dump it.