closed cooling heat exchanger maintenance

[33ec]

While doing routine maintenance prior to winterizing I was in the process of checking the antifreeze level and quality in my heat exchangers only to discover that my starboard engine heat exchanger developed a serious internal hole sometime between August and now. Turns out my heat exchanger was basically full of water. no warning sign-engine runs great and at regular temp. internally it rotted out. just a word of caution--check these things before winter. overlooking a simple fix such as this will surely cause a frozen and cracked engine block. Not a cheap fix, about $1k for the proper replacement but cheaper than the $10k a new engine would cost to have installed.