How to Replace a Switch Temperature Sensor on a 302

Ford first produced the 302 small-block engine in 1968, and the engine was essentially a 289 with a slightly longer stroke. Unlike earlier engines, by 1968, Ford equipped each of its vehicles with an electronic temperature sender. The sender features a brass fitting on the bottom, which penetrates the top of the intake manifold and measures the temperature of the antifreeze that flows through the manifold. This brass fitting was prone to corrosion, which can minimize the sender’s ability to provide an accurate temperature reading. Fortunately, replacing the sender takes only a few minutes.

Things You'll Need

  • Wrench
  • Teflon tape
  • Pliers (if necessary)
  • Shut off the engine and allow it to cool.

  • Press down on the radiator cap while simultaneously twisting it in a counterclockwise direction until the cap disconnects from the radiator.

  • The sender is located at the front of the driver’s side of the intake manifold. A single wire slides onto a threaded pole on top of the sender. Pull the wire off of the pole.

  • Twist the sender in a counterclockwise direction with a wrench until you can pull the sender out of the intake manifold.

  • Wrap the threaded end of the replacement sender with Teflon tape.

  • Lower the sender into position on top of the intake manifold, then tighten the sender into the manifold by twisting it in a clockwise direction with a wrench only until the sender is snug. Take care not to over tighten the sender, which can damage it.

  • Press the rubber boot on the end of the sender’s single wire onto the threaded pole on top of the sender. If the boot not grasp the threaded pole securely, gently crimp the boot in place with pliers. Inside the rubber boot is a metal fitting, which will conform to the threaded pole.

  • Position the radiator cap into place on top of the radiator, then press down on the cap while twisting it in a clockwise direction until the cap snaps into place.