Honda FourTrax Foreman Rubicon TRX500FA5 2019 Owner's Manual page 166

Coolant
To clean the radiator core and radiator grill plate:
1. Remove the radiator cap lid (page 153).
2. Remove the reserve tank (1) by removing the bolt (2) and clips (3)
(page 133).
3. Release the hoses (4) from the guides.
4. Hold the reserve tank being careful not to spill the coolant.
LEFT FRONT
(2)
(3)
(1) reserve tank
(2) bolt
156 Servicing Your Honda
(1)
(4)
(3) clips
(4) hoses
(3)