Low Engine Idle Speed Causes Excessive Vibration Caterpillar

Problem:

Excessive engine vibration may occur in TH62, TH63, TH82, and TH83 Telehandlers. Some early TH62 Telehandlers vibrated so severely that the cab also vibrated.

Solution:

Inspect engine mount assemblies for wear and verify engine idle speed.

1. Inspect 8T-4136 Bolt (1) for looseness and contact with plate (2). Replace bolt if damaged. Bolt is tighten to a torque of 40 N·m (29 lb ft). See illustration.

2. Inspect all 122-4477 Flexible Mount Groups for wear and 8T-4176 Bolt (3) for looseness. Replace if necessary. The bolt (3) is tightened to a torque of 50 N·m (37 lb ft). See illustration.

NOTE: The 122-4477 Flexible Mount Groups are not serviced as a group. The 122-4477 Flexible Mount Groups are composed of the following servicable parts: 122-4479 Mount Assembly, 122-4480 Overload Washer, 122-4481 Rebound Washer.

3. The engine idle speed should be adjusted to the following:

Typical Engine Mount Assembly

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