Drive Belt

NOTICE: Loose belts result in slippage that can cause belt and pulley "glazing" and inefficient compound operation. Once a belt has become "glazed," replace the belt. Loose belts can also place high impact loads on the driven component bearings due to the whipping action of a loose belt. Overly tight belts can lead to bearing damage and early belt failure.

Replace a frayed or cracked belt. Ensure that the belt tensioning devices are operational. Do not use drive belt dressing in order to extend belt life.

Examine the pulleys for chips, nicks, tooth marks, cracks, bent sidewalls, corrosion or other damage. Use the following steps in order to check the pulley alignment.

1. Place a straight edge, or position a cord, across the two pulleys so that they touch at all points
2. Turn each pulley one-half revolution and recheck. The straight edge or the cord must make full contact at all points.

If contact is not made at all points, the pulley may be warped or its shaft could be bent. Replace any damaged parts.

NOTICE: A worn head gasket may allow exhaust gases to leak into the cooling system. This can damage the cooling system as the gases combine with the water to form caustic acids which are harmful to the radiator and the engine.

Use the following procedure in order to check for exhaust leaking into the cooling system.

1. Drain the system until the coolant level stands just above the top of the cylinder heads.
2. Disconnect the radiator upper hose.
3. Remove the thermostat and the coolant pump drive belt.
4. Start the engine. Accelerate several times. Note any measurable coolant rise or the appearance of bubbles that may indicate that exhaust gases are leaking into the cooling system.

1. Remove large obstructions blocking the radiator or the condenser.

•	Auxiliary oil cooler.

•	Spare tire

•	Ice, mud or snow obstructing the radiator fins

2. Engine oil may be overfilled.
3. Incorrect radiator for the application.

Check the part number on the radiator.

4. Loose, damaged or missing air seals.
5. Incorrect injector timing.

1. Incorrect or damaged fin.
2. Worn or damaged emission system components.

•	Possible overheating when the vehicle is idling.

•	Damaged crankcase depression regulator (CDR) valve.

3. Pressure check the cooling system with the pressure cap installed. This will indicate if the pressure cap leaks because of radiator filler neck damage.
4. Worn or damaged coolant pump.

•	Impeller vanes eroded or broken.

•	Worn or damaged bearing and/or seal. Check for shaft or bearing play.

5. Plugged radiator tubes.

Perform a flow check.

6. Internal system leaks.

•	Head gasket

•	Cracked engine block

•	Timing chain cover

•	Intake manifold gasket

7. Plugged coolant passages in the cylinder heads. Perform a visual check.