My first time out in this old "new to me" 1987 Mercruiser 165 4 cyl. gradually heated up to 200 degrees before a hose burst. Got the boat home and pulled the riser off to reveal that the water ports leading to the exuast manifold were really clogged. The local marine store reccommended that I soak both the riser and the exaust manifold in half water and half muratic acid. They have been boiling for four days now like a witches brew. Does this sound like the right process to clean them out? This is a Florida boat and was use in saly water alot I assume. It probably was not flushed as it should have been. It has a 4 inch exchanger and new impeller. Idled fine on muffs, no over heating. Thanks for any imput.
