Checking Crankshaft Vibration Damper

NOTE: This service should be done every 500 hours.

IMPORTANT: Even if they continue to function, replace crankshaft vibration dampers every 4500 hours or 5 years, whichever occurs first; to do so “consult your John Deere dealer”.

RG7369-UN-05JAN98

The engine has dual dampers. Make same checks on each damper.

1. Remove belt (shown removed).

2. NOTE: Always replace both dampers as a matched set.

   Grasp vibration damper with both hands and attempt to turn it in both directions. If rotation is felt, damper is defective and should be replaced.

3. NOTE: Check the offset on the internal damper. Always replace both dampers as a matched set.

   
   RG7370-UN-05JAN98

   Check vibration damper radial runout by positioning a dial indicator (A) so probe contacts damper outer diameter.

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4. Rotate crankshaft using JDG820 Flywheel Turning Tool.

5. Note dial indicator reading.

   Item	Measurement	Specification
   Damper	Maximum Radial Runout	1.02 mm (0.040 in.)

   If offset exceeds specifications, replace vibration damper.