Over heating engine

Checklist for an over heating engine

Why is my engine overheating?

1.   Is the engine actually overheating or is the gauge reading high

2.   Is the engine oil level correct

3.   Is the oil milky or caremel

  • If yes check items 11 to 13

4.   Does the engine over heat at low or high speed (if items 2 to 10 are OK )

  • Low speed over heat is usually air flow Check items 3, 12 to 16
  • High speed over heat is usually water flow Check items 11 & 20

5.   Is the coolant still OK or does it need replacing

  • Check coolant quality with test strips or spectrometer

6.   Is the fan belt intact & working

7.   Is the thermostat working correctly

8.   Is there any visible water lose

9.   Is the coolant level correct in the reservoir

10.  Is the coolant level correct in the radiator

11.  Is the radiator cap holding correct pressure

12.  Is the cooling system holding pressure

  • If system is not holding pressure check for leaks out of hoses, water pump, gaskets etc.
  • If not visible externally remove spark plugs and check for water in cylinder Check sump & in tappet cover area for water leaks

13.  Is the cooling system building pressure when the engine is running

14.  If the cooling system is not building pressure check items 4,5,8,9,21, & 22

15.  Is the cooling system pressure to high

  • Check for blown head gasket or blocked radiator

16.  Is the radiator & cooling system scale free & clean

17.  Is the air dam still intact

18.  Is the airflow free from obstruction

19.  Is the fan working

20.  Is the fan drawing enough air (viscous hub )

21.  Is the fan on the correct way

22.  Is the exhaust free from obstruction

23.  Is the timing correct

24.  Is the fuel mixture correct

25.  Has the water pump been replaced or need replacing

26.  Is the heater core leaking