I have a 1998 suburau outback legacy and I have changed the radatior and had the motor flushed and changed the thremnostat and it still runs hot. the head has been checked for leaks. When i have taken it in for repairs the car runs well for a while but after about 100 miles it runs hot again. Is it possible that the water pump just works part of the time?
Replace the water pump along with the upper and lower radiator hoses if you already have not done those. If the pump has never been replaced don’t even think about it, do it.
Has the timing belt ever been replaced? Was a new water pump installed with the timing belt?
If the answer to the above is “no,” it’s time to replace both.
Also check if the radiator cooling fan is working properly.