Tech Tip: How to Diagnose Overheating with Thermodynamics and Data
Modern engine overheating issues aren’t always caused by a bad radiator. In this Tech Tip, Motor Age technical and multimedia content director Erik Screeden demystifies the thermodynamics behind today’s cooling systems and offers a diagnostic approach every technician should master.
Learn why radiators rely on more than just coolant and airflow, and how factors like ambient temperature, fan performance, coolant flow, stack contamination, system design and engine load all affect heat transfer. You’ll discover how improperly functioning fans, stuck grille shutters, dirty condensers or even air pockets can sabotage cooling, even with a brand new radiator.
Erik walks you through a comprehensive diagnostic process using thermal imaging, scan tools and surface temperature readings to pinpoint whether the real culprit is airflow, coolant flow, system blockage or environmental overload. He also explains why a radiator might be undersized for the vehicle’s demands, especially under high-stress conditions like towing, stop-and-go traffic or extreme heat.
If you’ve ever replaced a radiator only to have the vehicle still overheat, this video is for you. Watch the full segment to gain critical insights and practical steps that go beyond parts replacement, giving you the knowledge to solve tough cooling issues with confidence.
About the Author
Erik Screeden
Technical and Multimedia Content Director
Erik Screeden is the Technical and Multimedia Content Director for the Vehicle Repair Group. He has been in the automotive industry for over 24 years. During that time, Screeden was a technician. He started out at a Ford dealership and continued to several independent repair facilities as well as spent time in the specialty aftermarket where he had the opportunity to work at a GM-specific performance shop. After his time as a technician came to an end, Screeden transitioned into a role providing scan diagnostic and J2534 tool support. He was then able to parlay his experience as a technician and a support specialist and use that in several technical sales roles.