Looks like I`m losing coolant. I think its coming from the top of the rad. The overflow tube, seems to be just venting out. THe top of the hose is cracked. Pretty dry rotted, so going to try making a overflow bottle, and replacing the radiator cap. I havent noticed any sign of a blown gasket, and havent seen any leaks, so seems most likely?

 

Don't fill the radiator to the top. Minis seem to tosss out the top 1/2 inch or so anyway. Make sure the fluid covers the core inside by about an inch but leave some head space. Sounds like a weak cap if there are no other symptoms... What does the temp run?