Hey Guys,<br /><br />I have a 2001, 4.3 liter volvo-penta (GM) that I'm trying to winterize myself. I have located five drain plugs, a pair for the manifolds and a pair for the block, and one just in back of the upper pulley, all which I drained. I also found a convenient pipe plug near the top of the motor, which I believe is in the thermostat housing in which I can pour anti-freeze. What I don't know is what are the plugs on top of the exhaust risers ? They're exactly the same size as the one in the thermostat housing. Are these in the riser cooling jackets? Can I (should I) add a little anti-freeze to each to fill the risers/ manifolds cooling jackets?<br /><br />Also, how much antifreeze should I expect to pour into the block?<br /><br />Thanks for your inputs! 
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