Q: How to remove and clean the coolant expansion tank on Mercury Mountaineer?
A: Drain the cooling system. Disconnect the reservoir hoses by removing the spring clamps from the reservoir hoses and carefully twisting the coolant hoses off the reservoir. Plug the hose to prevent leakage. On 2006 and later models, the coolant reservoir is mounted on top of the Radiator. Remove the reservoir mounting bolts and lift the reservoir out of the engine compartment. Clean out the reservoir with soapy water and a brush to remove any deposits inside. Inspect the reservoir carefully for cracks. If you find a crack, replace the reservoir. Installation is the reverse of removal.