Checking Drive Belt

→ Only remove the drive belt when it is cold.

→ Replace damaged drive belt.

→ Following belt breakage, check adjacent components and the interior of the engine compartment for damage, and repair or replace damaged parts if necessary.

→ Find out why the belt broke. Check deflection rollers or crankshaft vibration balancer for prior damage.

→ If the drive belt is jammed, replace vibration balancer.

→ Disconnect power supply to the drive motor of components or to the battery.

Information 

• If spark plugs must be changed in the course of maintenance operations, the drive belt should be checked when the spark plugs are removed. The engine can then be cranked easier. 

Information 

• The following table indicates damage which necessitates replacement. 

Item	Type of damage	Explanation
-A-	Slight crack in a rib.	Drive belt is OK.
-B-	Hairline crack that runs across the entire belt width, or the butt seam is damaged.	Replace drive belt.
-C-	Crack running down to half of rib height.	Drive belt must be replaced if there is more than one crack running down to half of rib height.
-D-	Crack running to base of rib.	Replace drive belt.
-E-	Crack running to traction cord, or sides so worn that the traction cord becomes visible.	Replace drive belt.
-F-	Rib detachment	Replace drive belt.
-G-	Rib fracture	Replace drive belt.

1. Using chalk, mark the drive belt in the area around the tensioning roller. → Marking on drive belt 
   Fig 2: Checking Deflection Rollers For Smooth Operation

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
2. Turn engine at the vibration damper in the rolling direction using a socket wrench until the chalk mark is at the same place again. While turning at the crankshaft, check the drive belt at the deflection rollers for signs of damage.
3. When turning the engine, check deflection rollers for smooth operation, intact running track and play. Replace noisy and damaged rollers.