I push the washer button and the wipers go for a few seconds but no fluid reaches either the front windshield or the rear window. I can hear the pump, sounds like it is working. Tried to remove the hose from the washer reservoir but is difficult to do so in an attempt to force compressed air through the delivery lines. What can I do? The washer reservoir and the coolant reservoir appear to be a single unit. Do I have to remove that to get to the fluid line? Is that what I should be doing? Any advise?