Whenever I fill up my engine coolant tank it leaks out the back windshield wiper fluid hose basically when I turn the car off somehow the coolant gets pumped through the back windshield wiper sprayer and leaks all over my bumper then I go check my engine coolant tank and all of the coolant has been drained how do I stop this from happening and why does it happen

 

WHAAAAAAAAAAAAT?? We are going to need pictures of this one... Radiator overflow is on the passenger side of engine bay and wiper fluid reservoir is on the driver side correct?

(Sorry if my whaaaaaaaaat was a bit too dramatic)

 

My mistake I recently changed my thermostat on my blazer and filled up my engine coolant tank as well now when the car is stopped windshield wiper fluid leaks out the back windshield wiper sprayer onto my back bumper I made a mistake in saying engine coolant was leaking out of the windshield wiper rear but it's just fluid from the windshield wiper tank. these things never happen to my blazer before until I changed the thermostat why is this happening ? Is the engine somehow forcing The windshield wiper tank to flow out of the rear sprayer because of pressure in the engine what do you think ?

 

You should edit your original post as well (the description of the problem) I fixed the thread title for you