When you take a look at an engine, it can easily resemble a mass of wires and cables. However, one of the tools provided to assist in maintenance is the color coding of wiring. Wiring is standardized according to SAE regulations, of which Marinediesel is compliant. However, color codes between manufacturers may vary slightly from make to make.
Marine wiring is twisted pair, shielded, to minimize interference (EMF). It is required to be both oil resistant and able to withstand heat of at least 75° C.
There are a few minor differences between marine wiring and wiring intended for land vehicles, normally the fact that vessels require a higher gauge and extra moisture resistance due to their environment.
So, what are the color codes?
Marinediesel has numerous charts listing the color codes to specific engine components in our electrical manual, available for download.
Though there is some variation, as mentioned, between manufacturers, there are some general consistencies: