Initial Inspection and Diagnostic Overview
Inspection and VerificationCAUTION: To avoid personal injury, do not unscrew the coolant pressure relief cap while the engine is operating or hot. The coolant system is under pressure; steam and hot liquid can come out forcefully when the cap is loosened slightly. Failure to follow these instructions can result in personal injury.
CAUTION: Check the coolant level and engine oil, top off the coolant if needed, if there is engine coolant in the engine oil the cause must be corrected and oil changed or major component damage may occur.
CAUTION: All vehicles are filled with Motorcraft Premium Gold Engine Coolant VC 7 A (in California and Oregon VC 7 B, in Canada VC 7 C) or equivalent meeting Ford specification WSS M97B51 A1 (yellow color). Always fill the cooling system with the same type of coolant that was drained from the system. Do not mix coolant types.
NOTE: The addition of Cooling System Stop Leak Pellets VC 6, darkens Motorcraft Premium Gold Engine Coolant from yellow to golden tan.
NOTE: If Motorcraft Premium Gold Engine Coolant V C 7 A (in California and Oregon V C 7 B, in Canada V C 7 C) has a clear or pale yellow color, this indicates a higher water content than required.
1. Verify the customers concern by operating the engine to duplicate the condition.
2. Inspect to determine if any of the following mechanical or electrical concerns apply.
Visual Inspection Chart
3. If the inspection reveals an obvious concern that can be readily identified, repair it as necessary.
4. Inspect the coolant condition.
1 Inspect the coolant color.
^ If Motorcraft Premium Gold Engine Coolant V C 7 A (in California and Oregon V C 7 B, in Canada V C 7 C) has a clear or pale yellow color, this indicates a higher water content than required.
^ Dark brown could indicate unauthorized stop leak may have been used. Use Motorcraft Cooling System Stop Leak Pellets VC 6 or equivalent meeting Ford specification WSS M99B37 B6
^ A light or reddish brown color indicates that rust may be present in the cooling system. Flush the system and refill with the correct mixture of Premium Engine Coolant or Premium Gold Engine Coolant.
^ The addition of Cooling System Stop Leak Pellets VC 6, darkens Motorcraft Premium Gold Engine Coolant from yellow to golden tan.
^ An iridescent sheet on top of the coolant could indicate a trace of oil is entering the system.
^ A milky brown color may indicate that engine oil is entering the cooling system. If engine oil is suspected, the cause of the leak may be internal to the engine.
2 If the engine coolant appearance is acceptable, test the engine coolant freezing point with a fluid tester. The freezing point should be in the range of -50° F to -10° F. If the vehicle is driven in cold climates less than -34° F. it may be necessary to increase the coolant concentration to get adequate freeze protection.
^ Maximum coolant concentration is 60/40.
^ Minimum coolant concentration is 40/60.
3 Adjust coolant concentration and level if necessary.
^ If coolant is low, add specified coolant mixture only.
^ If the engine coolant tests too weak, add straight engine coolant until the readings are within acceptable levels.
^ If the engine coolant tests strong, remove the some of the engine coolant and add water until the readings are within acceptable levels.
5. If the concern remains after the inspection, determine the symptom(s). GO to Symptom Chart. Symptom Related Diagnostic Procedures