Today I flushed the system with Prestone Super Flush. The coolant was pretty nasty looking. I noticed that the flushing solution was foaming out of the overflow tube, with the cap on tight. It shouldn't have done that, since the cap seal is below the overflow hole. I replaced the cap with a 16 psi new cap, and filled with the proper mix of antifreeze. I did notice that I do see the coolant flowing over the coils of the radiator if I have the coolant level just above the top of the core and I run the engine at high idle. I mowed for about 45 minutes with no temp light and no other sign of overheating. I am keeping my fingers crossed.
