Harleydavidson Oil Cooler Installation

An oil cooler is not a stock option on any Harley-Davidson model; however, if you have increased the torque and horsepower of your motorcycle, it is important to cool the oil, as these changes cause a rise in oil temperature. An aftermarket oil cooler is a simple and effective addition to your Harley-Davidson. Once you install the oil cooler, the assembly will keep oil regulated to normal running temperatures.


1. Remove the bolts that hold the voltage regulator in place with a wrench. The voltage regular is located just in front of the motor in between the floorboards of your motorcycle. Allow the voltage regulator to hang down by the cable that connects it to the motorcycle.

2. Remove the oil filter by hand — allowing the oil to drip into a drain pan. Separate the halves of the oil filter adapter that came with your aftermarket oil cooler. Place the rear piece of the adapter in place on the 1-inch locknut where you removed the oil filter. Tighten the locknut with a wrench to secure the rear half of the adapter.

3. Install the screws — covered with Locktite — with a screwdriver to connect the other half of the adapter to the motorcycle.

4. Install the angled brackets included with your oil cooler onto the mounting studs of the voltage regulator. Place the bolt into the left side of the bracket but do not tighten at this time. Reinstall the voltage regulator onto the angled brackets and tighten the bolts with a wrench to hold the voltage regulator in place.

5. Place the ground wire from your oil cooler onto the stud on the right hand side of the voltage regulator. Place a nut over the stud and tighten with a wrench. Also tighten the bolt from the left side of the angled brackets installed earlier.

6. Install and tighten with a wrench the hardware and mounting screws through the cross-member and oil cooler.

7. Install the oil line provided with your oil cooler onto the filter adapter and tighten the clamps of the hose with a wrench. Install a new oil filter.

8. Determine the length of oil line you need and cut off the excess and discard. Connect the other end of the oil line to the oil cooler. Tighten the hose clamps with a wrench.

9. Route the red wire on the oil cooler up the frame to a switched power source. Remove the headlight by removing the screws that hold the trim ring surrounding the headlight with a screwdriver. Pull the headlight out and connect the red wire to the switched power source after you cut the wire to the appropriate length.

10. Reinstall the headlight and the trim ring. Tighten the trim ring screws with a screwdriver.

11. Place the oil cooler cover over the oil cooler assembly and tighten the screws that hold it in place with a screwdriver.