Harley Davidson coolant inspection is an important, yet often overlooked, service point on liquid cooled Harley Davidsons.
There are two radiators that can be found on Ultra models that support a cooling system. These small radiators are located within the left and right side lower fairings of the motorcycle. Also included in the right side lower fairing, is the cooling system reservoir. To access the Harley Davidson coolant reservoir, pry the center top of the access panel to release the retainers from the lower right fairing.
The Harley Davidson coolant bottle has two lines. Reference the angled full line to check fluid level when the motorcycle is resting on its kickstand. Verify that coolant level in reservoir is at or slightly above the COLD full line. If the level appears to be below the COLD line on the tank, remove the rubber fill plug and add (only) genuine Harley Davidson extended life antifreeze and coolant until the fluid level is at or slightly above the COLD line.
If the coolant reservoir is empty when the engine is cold, you will need to inspect the system for possible leaks. The motorcycle can lose coolant from a damaged coolant line/connection or coolant can be leaking into the motor. If one of these problems exist, it must be correctly repaired before the motorcycle is operated.
The coolant can also be tested with a coolant tester. Allow the motor and system to cool and remove the pressure cap. Place a few drops of coolant from the filler neck onto the prism of the coolant tester and hold the prism to light. The Harley Davidson coolant freeze point will be the mark where the dark area begins on the ethylene glycol temperature scale. Compare the freeze point of the coolant to the anticipated operating or storage temperatures. Replace if required and replace the pressure cap.