How to Backflush a Radiator in a 1988 Mustang
- 1). Install the backflush kit onto your Mustang inlet heater core hose. This will be the radiator hose from the top of your engine that runs through your firewall and into your heater core. Use a utility knife to cut the hose, install the "T" fitting that comes with your kit, and clamp it down tightly. This addition will remain in place for the life of your car.
- 2). Open the radiator cap and install the backflush kit's splash guard onto the opening.
- 3). Install first the backflow device and then the hose connector onto the "T" connector, than screw the garden hose on.
- 4). Drain your radiator by twisting open the drain plug or petcock on the bottom of your Mustang radiator. Allow all the fluid to drain into a 5 gallon bucket. At this point, turn the hose on and allow the water to flow into the hose "T" fitting inlet.
- 5). Start your Mustang while the hose runs, and turn on the heater inside of the car. This process will not only backflush your radiator, but the entire cooling system. Allow your Mustang to idle, and watch the water coming out of the top of the radiator. When it begins to run clear, turn off the hose and allow the cooling system to drain.
- 6). Remove the hose, the splash guard, the backflow preventer and cap the "T" fitting. Close the drain petcock on the radiator, than refill the radiator with a 50/50 mix of antifreeze and water. Recycle the drained radiator coolant at your nearest automobile service station.
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