The MGA was renowned for overheating. My MGA is no different, give me a warm day and a hard drive and it will overheat. The quick solution is to change the thermostat. Use a the 160F thermostat in the summer and the 185F thermostat in the winter.
I found that soda crystals or caustic soda is very good for cleaning
oily sludge from the cylinder block and radiator. Important thing
to remember is not to leave it in the system too long. Both substances
when mixed with water are very corrosive. They have been know to
eat through the radiator and connecting hoses. Be careful!
