Get the wiring diagram for Mercruiser coils and ensure proper installation and troubleshooting of your boat's ignition system.. The Mercruiser 120 Ignition Wiring Diagram is an essential tool for any boat owner who wants to maintain their engine in top condition. It outlines the various connections between the motor's various components, such as spark plugs, alternator, and the ignition switch, allowing for easy troubleshooting and repair.
![[DIAGRAM] 1972 Mercruiser 120 Wiring Diagram](https://schematron.org/image/1976-mercruiser-gm-120140hp-wiring-diagram-9.gif "[DIAGRAM] 1972 Mercruiser 120 Wiring Diagram")
Delco EST Ignition Wiring Diagram Engine Harness switch. The gray wire in the harness goes to gray coming off of the coil. Only For Mercruiser I/O When Timing This is only a guide, you as the installer are responsible for ascertaining the proper hookup for your application. This will give you the theory of operation, and is to be used only as a.. Learn how to wire a Mercruiser ignition switch with this detailed wiring diagram. Follow step-by-step instructions to ensure proper installation and troubleshooting of your boat's ignition system.