challenger wrote:The discussion on pressurized cooling systems is all valid and interesting, but I still wonder how many work situations today's Cubs are subjected to that necessitates gaining a few more degrees of cooling capacity beyond that provided by the unpressurized system. The most important items are making sure your radiator and internal engine water jacket are clean, using a good rust inhibitor anti-freeze, and maintaining the proper coolant level in the radiator. Considering the age of the Cub, including the radiator and gaskets, it is my opinion that most owners will experience less trouble overall if they stay away from pressurizing their system.
Can't agree with you more, the reason both my old cubs have had their 7 pound pressure caps that were installed by the previous owners modified.
With the ratio of cooling capacity (onboard coolant reserve, core size, and air flow) to cubic inches of displacement, one would think the engineers had a good grip on the maximum amount of heat that could be produced under full load on a hot day but as previously brought to light, horsepower hungry attachments not originally available and thin air in the mountainous regions caused the engineers to rethink the possibility of the points between hot and boiling had become too close, making the change to the pressurized cooling system.