Initial Inspection and Diagnostic Overview

PRELIMINARY CHECKS

ENGINE COOLING SYSTEM OVERHEATING
Establish 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
^ Trailer towing
^ Steep grades
^ Any accessory addition that fully or partially blocks the grille opening

Driving techniques that avoid overheating are:
^ Idle with A/C off when temperature gauge is at end of normal range.
^ Increase engine speed for more air flow is recommended.

1. TRAILER TOWING:
Consult Trailer Towing section of owners manual. Do not exceed limits.
2. 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.
3. 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).

NOTE: If investigation reveals none of the previous items as a cause for an engine overheating complaint, refer to Cooling System Diagnosis charts.