The coolant efficiency is not up to specs which are mostly due to clogged radiators, thermostat not opening fully or closing, clogging of water passages, weak water pump or cooling fan.
If flushing is by means of using a water hose to run water through, it is not the correct way. The top or bottom tank has to come off and the fins checked visually and cleared. If 40 % of the core is clogged, the water running through it would still be fast. Some radiators gets clogged up not due to rust or muck. Chemical reactions from mixing different brands/types of coolant would clog radiator cores and the end result would be enamel like substances that are very hard and impossible to be removed. The only solution for such cases is to replace the radiator.
Did you check the radiator cooling fns for clogging? Insufficient air being drawn past the radiator can result in overheating, especialy under load conditions.
Apart from the radiator, is the cooling fan drawing strong air when running?
The overheating would cause the water tank to expand.
Wednesday, July 20th, 2011 AT 4:31 PM