Proper grounding for vehicle and engine electrical systems is necessary for proper vehicle performance and reliability. Improper grounding will result in uncontrolled and unreliable electrical circuit paths.
Uncontrolled engine electrical circuit paths can result in damage to main bearings, crankshaft journal surfaces, and aluminium components.
Uncontrolled electrical circuit paths can cause electrical noise which may degrade vehicle and radio performance.
To insure proper functioning of the vehicle and engine electrical systems, an engine-to-frame ground strap with a direct path to the battery must be used. This may be provided by way of a starter motor ground, a frame to starter motor ground, or a direct frame to engine ground.
In any case, an engine-to-frame ground strap is recommended from the cylinder head grounding stud to the frame and negative battery post.
Cylinder Head-To-Battery (-) Ground
Alternate Cylinder Head-To-Battery (-) Ground
The cylinder head must have a wire ground to battery as shown in the above illustrations.
Ground wires/straps should be combined at ground studs dedicated for ground use only. At “Every 12,500 miles (20 125 km) or 250 hours,” Inspect/Check all engine grounds. All grounds should be tight and free of corrosion.
The engine alternator should be battery (-) grounded with a wire size adequate to handle full alternator charging current.