Initial Inspection and Diagnostic Overview
ENGINE COOLING SYSTEM OVERHEATINGEstablish what driving conditions caused the complaint. Abnormal loads on the cooling system such as the following may be the cause:
PROLONGED IDLE, VERY HIGH AMBIENT TEMPERATURE, SLIGHT TAIL WIND AT IDLE, SLOW TRAFFIC, TRAFFIC JAMS, HIGH SPEED OR STEEP GRADES.
Driving techniques that avoid overheating are:
- Idle with A/C off when temperature gauge is at end of normal range.
- Increasing engine speed for more air flow is recommended.
Trailer Towing:
Consult Trailer Towing section of owners manual. Do not exceed limits.
Air Conditioning; Add-On Or After Market:
A maximum cooling package should have been ordered with vehicle if add-on or after market A/C is installed. If not, maximum cooling system components should be installed for model involved per manufacturer's specifications.
Recent Service Or Accident Repair:
Determine if any recent service has been performed on vehicle that may effect cooling system. This may be:
- Engine adjustments (incorrect timing)
- Slipping engine accessory drive belt(s)
- Brakes (possibly dragging)
- Changed parts. Incorrect water pump or pump rotating in wrong direction due to belt not correctly routed
- Reconditioned radiator or cooling system refilling (possibly under filled or air trapped in system).
These charts are to be used as a quick-reference only.
Cooling System Diagnosis Chart:
Cooling System Diagnosis Chart:
Cooling System Diagnosis Chart:
Cooling System Diagnosis Chart:
Cooling System Diagnosis Chart:
Cooling System Diagnosis Chart:
COOLING SYSTEM DIAGNOSIS CHARTS