Herein is the picture of diesel tachometer wiring instruction/installation for diesel magnetic proximity sender type. The tachometer is designed to operate only in 12V negative ground electrical systems with suitable magnetic proximity sender is equipped.
In addition of Magnetic Proximity Sender, No.16 stranded insulated wire and insulated terminal lugs are required to complete the installation.
You may have the wiring instructions you can download in pdf filetype. It contains informations such preparation, determining range selector switch position, Sender installation, Gauge installation, Connection of wiring, Calibration and adjusment of the tachometer(source: teleflexmarine.com).
