Mechanic have already check the main clutch fan and electric fan first before advising me for the thermostat.
Looks like this weekend i should be getting my radiator flushed and cleaned from inside completely.
Good heads up iRoc, you def Roc. Thanks a lot.
1998 Discovery is overheating for that I got the thermostat changed ,but also noticed that the heater is not working.
what do i do to fix the overheating thing.