4JH2TE - Water Flow Issues - Heat Exchanger Removal?

[Puesta del sol]

Looking for someone who has removed the heat exchanger - suggestions, tools, manuals? Order of removal etc.

Can I remove this after I have winterized for the winter? Thinking since I am removing the part I can drain anti-freeze from this part of the systems as well as the fresh water (currently winterzed).

Any help would be greatly appreciated.

 

[MitchM]

When you remove ht exchr from yanmars 2 3 or 4 cylndr you lose all antifreeze. Yans have 2 end pieces on ht excgrs held on by bolts. You need metric wrenches for bolts. Yans also have special gaskets which usually tear to pieces when you remove the end caps so get some automotive form a gasket in a tube. You will apply this in very thin layer to create good seal when you put back the end caps. (Or order custom gasket from yanmar $$ and time.) When you remove ht exc caps you can gently push out the core made of thin metal tubes. Shine a flashlite in, see if any tube is clogged by a piece of broken raw water pump impeller which is usual cause of engine running too hot. Clean out using thin wood chopstick or thin brush etc. Look up diagram of heat e xchrr in yanmar parts manual for yr engine and you ll see the size of wrenches needed for each bolt. If yr going to do this might as well run a cleaner thru the antifreeze system too as you ll need to replace all anti freeze... you might be able to find the service manual and parts manual for yr engine on line, they are worth having. Check boatdiesel.com , they used to allow a free download.

 

[Terry Cox]

Thanks for the very useful reply, Mitch.

 

[Puesta del sol]

When you remove ht exchr from yanmars 2 3 or 4 cylndr you lose all antifreeze. Yans have 2 end pieces on ht excgrs held on by bolts. You need metric wrenches for bolts. Yans also have special gaskets which usually tear to pieces when you remove the end caps so get some automotive form a gasket in a tube. You will apply this in very thin layer to create good seal when you put back the end caps. (Or order custom gasket from yanmar $$ and time.) When you remove ht exc caps you can gently push out the core made of thin metal tubes. Shine a flashlite in, see if any tube is clogged by a piece of broken raw water pump impeller which is usual cause of engine running too hot. Clean out using thin wood chopstick or thin brush etc. Look up diagram of heat e xchrr in yanmar parts manual for yr engine and you ll see the size of wrenches needed for each bolt. If yr going to do this might as well run a cleaner thru the antifreeze system too as you ll need to replace all anti freeze... you might be able to find the service manual and parts manual for yr engine on line, they are worth having. Check boatdiesel.com , they used to allow a free download.

Thanks. This is helpful, I guess one of my questions - If I take if off the boat now and clean over the winter, is there an issue with having it off the engine? I am thinking I would cover the exposed engine are on the boat with plastic.