Exhanger OK
Joe, settle back and relax a little, and study the system. If you have an engine manual and/or boat manual, look at the diagrams Your heat exchanger which is mounted on the engine should have antifreeze in it from the factory. It is a "closed system" meaning fresh water from the lake and antifreeze (coolant) from the system do not mix. Water comes in through your thru-hull, runs through the heat exchanger, thus cooling the antifreeze that is in the closed system. The antifreeze circulates through the engine, cooling the engine. The antifreeze coolant recycles throught the heat exchanger to keep cool. On my old boat I installed a Tee fitting in the line between the through hull and the engine (close to the through hull) Off the Tee I had a ball valve, and from the ball valve was a clear hose. With the engine running, I stuck the clear hose in a bottle of NON-TOXIC antifreeze (NTA). Now with the new ball valve open, close your thru-hull. The NTA will now be sucked into the system. About one gallon should be enough. If your able assistant can see the wet exhaust, they can shut down the engine when NTA starts coming out. Now close all valves and you are done. Savy?
