3406E, C-10, C-12, C-15, C-16 Truck Engines Caterpillar

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(1) 3406E cylinder head ground stud

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(2) C-10 and C-12 cylinder head ground stud

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(3) C-15 and C-16 cylinder head ground stud

Inspect the OEM vehicle wiring harness for the following conditions:

• Connections that are loose or disconnected

• Mounting hardware that is missing

• Insulation that is chafed or cut

• Wires that are bare

The cylinder head grounding stud must have a wire ground to the battery. Tighten the cylinder head grounding stud at every oil change. Ground wires and straps should be combined at engine grounds. All grounds should be tight and free of corrosion.

1. Clean the cylinder head grounding stud and the terminals for the cylinder head ground strap with a clean cloth.

2. If the connections are corroded, clean the connections with a solution of baking soda and water.

3. Keep the cylinder head grounding stud and the strap clean and coated with MPGM grease or petroleum jelly.