Delco 28Si Wiring Diagram. This connects to the “s” terminal. Web replacement parts instructions 18si, 24si & 28si; delco 28si alternator wiring diagram from wireenginenichols.z21.web.core.windows.net Web little known facts about wiring schematic diagram. Usa 800 854 0076, mexico 01 800 000 7378, brazil 0800 703 3526,. Web instruction sheet 10524919 07jl14 rev3 24si™ alternator installation.