Originally Posted by bluebear_691
I just installed a new radiator in my 89 Taurus SHO. When I started it and put in water it was bubbling. The fan isn't kicking on. What's the bubbles mean and why isn't the fan turning on???
When you fill the cooling system up, air is being displaced. This is the bubbles you are seeing. You fill it to the top of the neck and let the bubbles come up, then refill it. Keep doing this until the coolant stops going down so much. Then start the engine and let it idle with the cap off. Keep the coolant slightly below the neck to allow for the larger bubbles to come which will push the coolant out of the neck. (It will just rise up a little, keep a bucket under the R.F. corner of the car.) When the thermostat evetually opens, the coolant will go down again. Top of to the top of the neck, put the cap on, and fill the overflow bottle to slightly above the hot level. Raising the engine RPM and squeezing the upper hose helps too.