4-108 cooling system

[balthazor]

I have a shop manual for the 4-108 and it tells me how to drain
the cooling system so I can replace all the coolant. But it
assumes I know where the main drain is and just tells me to open
it. Well, I don't know where it is, so I am lost. Can anyone
help? And, do I really have to loosen the "square" bolts on the
top of the engine to get the system to drain completely? Sounds
quite complicated, as the manual describes it. Thanks.

 

[akopac]

<div>Terry,Did you ever get an answer to your question. I changed the coolant in my boat last weekend and couldn't find a drain on the engine block either. I ended up pulling the drain on the heat exchanger for a partial change only. Eric
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