QuestionI have a 1988 Corvette with 70K miles. The temp in traffic goes to low 200s and when on the highway drops to low 170s Is this range an indication that I need to change the thermostat, flush the radiator, both?
AnswerHi Bill Faulk,
This could indicate a plugged cooling system. Flush the system. To do this properly, you should remove the thermostat. It will get debris plugged in it otherwise. Replace it with a new one. May or may not help. Depends on how plugged the radiator is. 212 degrees F is an ideal temp for a V-8. However, if it is higher than normal, then it indicates a problem.
An often overlooked possibility is the cooling fan clutch. Is your cooling fan electric? If not, test the clutch by grabbing a fan blade and slightly moving it clockwise and counter-clockwise. You should feel a pretty good drag. If not, it may be free floating and not spinning enough.
Another possibility is the radiator cap. If this is failing, the overflow bottle cannot work properly.
At 70K, it is time for a flush and fill anyway. After 2 years, the coolant turns acetic. It will corrode internal motor parts.
Hope this helps.
C J S
