Overheating/Removing heat exchanger on Westerbeke 30 (4-91)

[Mary Mac]

My boat's engine will overheat if I run at a reasonable cruising RPM. (I don't have a tach). Had to move the boat across from San Mateo to Alameda at about 3.5 knots the other day to keep the water temp cool. It is cooling, just not sufficiently. There is a good amount of water exiting at the stern. I was thinking about removing the heat exchanger to get it boiled out or check for blockage, but I'm not finding much info about how to remove it. It looks like a total pain to access. Any tips? Joe?

[rcvesselstyn]

Hi Mary, I sent you a couple of links that discuss the overheating problem and some solutions. They also have links to mechanics manuals. I have not had that engine, however from past experience I would be looking for air in the line or a damaged fresh water impeller. Of course if you're careful you can always take the end caps off and flush it out, it just makes a huge mess. Good luck!

[Jedsail]

Hello Mary - to solve any overheat problem, one must look at the complete cooling system, not just one part, such as the heat exchanger.
There are MANY reasons and combination of reasons for an engine to overheat. Start with the raw water intake and proceed along the flow of water, checking for details and problems. You must know DIFINITIVELY the condition of each part before moving along to the next potential problem. For example - when was the last haulout, and was bottom paint applied INSIDE the thru hull? Does the c-cock open all the way? Do all hoses between the ocean and the raw water pump have wire wound construction? [ if not, they may collapse under pump suction ] Are all gaskets in the raw water strainer present, and pliable, so they seal properly? Does the raw water pump need rebuilding?
Are there any vanes missing from the impeller? Is the cover gasket sealing correctly? ETC ETC. Call me with questions - 860 666 2184
Joe DeMers

[Mary Mac]

Thanks for sending me those links, Randy. They are helpful.

Thank you, Joe. I will give you a call.

[rcvesselstyn]

Well of course Joe is absolutely correct. I made the assumption that your statement "a fair amount of water exiting the stern" indicated that the raw water system was satisfactory. My bad.

[Mary Mac]

I made the same assumption!