Overheating

chevrolet
trailblazer

#1

2003 trailblazer inline 6 overheating in stop and go traffic

fanclutch and tstat has been replaced for the 4th. time. never has

fixed the problem. It has been checked out by the dealer.

no luck.


#2

Has anyone checked the radiator for internal restriction? If the radiator is partially restricted, it’s cooling capacity is reduced. This become mores evident when the vehicle is in stop and go traffic as radiator fan doesn’t move as much air past the radiator as driving at speed, and the water pump slows down as the engine speed slows down.

The radiator can be checked for restriction by pointing an infrared thermal gun at the cores of the radiator. Those cores that are much cooler than the rest are the ones that are restricted.

Tester