Re: winterizing merc 170
Reiterating what JKopec said....<br /><br />Assuming you are referencing the 3.7L (224 cubic inch) closed cooling engine. No need to get anti freeze into engine, raw water never enters engine.<br /><br />Drain the heat exchanger by removing drain plug on bottom. There should be two plugs, the rear most is raw, the other is antifreeze (closed side) If you start to see antifreeze, you've got the wrong drain. Drain the raw (rear plug). Also disconnect one of the hoses going through the water cooled voltage regulator (if still in place, to drain out anything from this low point. Finally, check for water cooled lines to power steering (if quipped), disconnect at cooler (low point). Lower the drive unit...and that's it. Everything will gravity drain, very easy. Twelve years, never a problem in this very cold climate. Check antifreeze with hydrometer, like you would for an automobile...I change antifreeze every other year.
