4
5. Connect the Green/Black wire of the relay harness to a switched 12V source.
6. Connect one of the red wires of the relay harness to the positive wire (red wire) of the fuel pump.
7. Connect the black wire of the fuel pump to a good clean chassis ground using a ring terminal.
8. Attach the in-line fuse holder to the remaining red wire. After attaching the fuse holder, insert a 25A fuse and connect to the positive side of the
battery using 12 gauge wire.
9. Reconnect the battery cables.
Figure 2
(2) WIRING THE FUEL PUMP WITH AN OIL PRESSURE SAFETY SWITCH AND RELAY:
One method is to wire the pump to a switched 12-volt source (providing power only when the engine is running) located at the vehicle’s electric panel.
To ensure this condition, the installation of a Holley 12-810 oil pressure safety switch is recommended for installation into the wiring circuit. This will
ensure that the pump will not continue to operate after the engine is shut off and/or when the key is left in the “ON” position. If the pressure switch is to
be used, follow the installation instructions as outlined below (refer to Figure 3). Use 12 gauge wire for power (BAT+) and ground wires.
1. Disconnect the cables from the battery.
2. Remove the original equipment oil pressure switch and retain.
3. Screw a 1/8” pipe nipple into the hole from which the original pressure switch was removed. Use any suitable thread sealant on all fittings, taking
care to avoid any excess that might contaminate the engine.
4. Screw a 1/8” pipe tee onto the nipple and position it in a manner to facilitate the installation of the original oil pressure switch and the new oil
pressure safety switch in the remaining two holes.
5. Screw in the two switches and reconnect the lead to the original equipment oil pressure switch.
NOTE:
The pump oil pressure switch will normally have three terminals marked: C (common), NC (normally closed), and NO (normally open).
