EXCESSIVE FUEL CONSUMPTION (Cont.)
|
Engine
Perform an engine compression test to determine which mechanical component of the engine is at fault.
Check valve clearance adjustment.
|
Cooling system
Check thermostat operation and heat range.
Transmission
Check band alignment (automatic transmissions).
|
ENGINE OVERHEATS
|
Temperature sending unit
and gauge
Unit or gauge defective (not in-dicating correct temperature), or constant voltage regulator defective.
Engine
Cylinder head bolts not properly torqued.
Incorrect valve clearance.
Low oil level or incorrect visco-sity oil used.
|
Cooling system
Insufficient coolant.
Cooling system leaks.
Drive belt tension Incorrect.
Radiator fins obstructed.
Thermostat defective.
Thermostat improperly installed.
Cooling system passages blocked.
Water pump Inoperative.
Ignition system
Incorrect ignition timing.
|
LOSS OF COOLANT |
Cooling system
Leaking radiator
Loose or damaged hose connec-tions.
Water pump leaking.
Radiator cap defective.
Overheating.
Engine
Cylinder head gasket defective.
|
Intake manifold to cylinder head gasket defective.
Cylinder head or Intake manifold bolts not properly torqued.
Cylinder block core plugs leaking.
Temperature sending unit leaking.
Cracked cylinder head or block, or warped cylinder head or block gasket surface
|
ENGINE FAILS TO
REACH NORMAL OPER-ATING TEMPERATURE
|
Temperature sending unit and gauge
Unit or gauge defective (not indi-cating correct temperature) or con-stant voltage regulator defective.
|
Cooling system
Thermostat Inoperative or of in-correct heat range.
|
NOISY HYDRAULIC
VALVE LIFTERS
|
A noisy hydraulic valve lifter can be located by operating the engine at idle speed and placing a finger on the face of the valve spring retainer. If the lifter is not functioning prop-erly, a shock will be felt when the valve seats.
Another method of identifying a noisy lifter is by the use of a piece of hose. With the engine operating
|
at idle speed, place one end of the hose near the end of the valve stem and the other end to the ear and listen for a metallic noise. Repeat this procedure on each intake and exhaust valve until the noisy lifter(s) has been located.
The most common causes of hy-draulic valve lifter troubles are dirt, gum, varnish, carbon deposits and
|
**
