I have a question regarding zinc's on a Yanmar 2GMF engine. Are there any in the heat exchanger of the 2GMF? I have read some threads that this is a part of the annual inspection. A Yanmar rep. told me there aren't any on this engine. I find that odd. I have never inspected mine since purchasing our 87 Hunter 31 in 2004. It sounds like an inspection I need to start doing. Our sailing area is fresh water.
Some history to offer. One year after purchase I opened the coolant cap and noticed a large, perfectly round dark color ball floating in the anti freeze. I managed to get it out and found it to be very soft. (Like old rubber, or gum.) I called Yanmar and asked a Tech if he had ever seen anything like that before. He said no. I asked him if he though it could be part of the fresh water impellar that has come lose, or an "O" ring that has desolved. No to both questions. His opinion is it may have been some radiator stop-leak. Can't iimagine the PO doing this. So for the last 2 years I have experienced low coolant level in the engine from time to time. And more coolant in the overflow bottle than should be. No visiable leaks on engine, or on the paper I put under the engine to detect a leak.
So I am trying to determine if I have a heat exchanger problem, or a head gasket problem. I just received all repair parts in the mail to do this project, and was looking for some advice from fellow sailors who may have information to offer on this great web site. Thanks for your time gentleman. Fair Winds to all.
Some history to offer. One year after purchase I opened the coolant cap and noticed a large, perfectly round dark color ball floating in the anti freeze. I managed to get it out and found it to be very soft. (Like old rubber, or gum.) I called Yanmar and asked a Tech if he had ever seen anything like that before. He said no. I asked him if he though it could be part of the fresh water impellar that has come lose, or an "O" ring that has desolved. No to both questions. His opinion is it may have been some radiator stop-leak. Can't iimagine the PO doing this. So for the last 2 years I have experienced low coolant level in the engine from time to time. And more coolant in the overflow bottle than should be. No visiable leaks on engine, or on the paper I put under the engine to detect a leak.
So I am trying to determine if I have a heat exchanger problem, or a head gasket problem. I just received all repair parts in the mail to do this project, and was looking for some advice from fellow sailors who may have information to offer on this great web site. Thanks for your time gentleman. Fair Winds to all.