CAP 5K7827 - Caterpillar

Grounding (Minus Battery Bus Bar Connections)
All negative battery connections MUST have a common ground that terminates at the -Battery Bus Bar. Improper grounding will cause uncontrolled and unreliable circuit paths.
This can result in damage to the engine crankshaft main bearings, crankshaft journal surfaces or other engine components. This may also cause electrical activity which may degrade vessel electronics and communication equipment. Refer to Battery Circuit Requirements and Considerations: Grounding in this guide for additional information. Proper grounding for vessel and engine electrical systems is necessary for engine/vessel performance and reliability. The problems with intermittent power connections are often very difficult to diagnose and repair.
The alternator, starting motor, and all electrical systems MUST be grounded to -Battery. The alternator and starting motor must also meet marine isolation requirements. For engines which have an alternator grounded to an engine component, a ground strap MUST connect that component to -Battery and the component MUST be electrically isolated from the engine.A Bus Bar with a direct path to -Battery is permissible and recommended to use for all common ground connections. Refer to Power Supply Connection to start (Ignition) Switches and Starting Power Supply Connections to Start (Ignition) Switch (es) in this guide for additional information.