I took off the heat exchanger to clean out the tubes. but it seems that both ends are solid. how do you clean the heat exchanger ? also I seem to have two zinc ports, however the small one won’t fit the sink (the tubes are in the way) the other is much larger and is past the tubes.
If you have a radiator shop in your area, they can boil it out. Id test for leaks before reinstalling as this looks to be a pretty old heat exchanger. If you are in the market for a new one, Lenco on Long Island, NY can build a replacement based on your existing one. I’ve used them and know others who have. I can’t remember what I payed. But it was probably about $200+.